2012 Mercedes-Benz B-Class UK Version

The world-best aerodynamics of the new Mercedes-Benz B-Class were honed with the help of complex computer calculations and flow simulations. Models and prototypes spent around 1,100 hours in the wind tunnel, and more than 275,000 computer hours were invested in digital airflow simulation.

One aerodynamic trick is worthy of special mention: the patented advanced front wheel arches which channel air over the front wheels. These innovative serrated spoilers combine with slots in the wheel arches and aerodynamically optimised hubcaps to considerably reduce flow losses.

Equally comprehensive measures ensure a smooth airflow along the underbody. The floor features extensive cladding up to the rear wheel arches, followed by additional cladding around the rear axle. Even the rear silencer has undergone aerodynamic tuning.

The ECO Technology package which will be an option on all versions of the B-Class lowers the ride height, seals the rear window joints and adds cladding to the rear chassis components.

High-quality materials and finely structured surfaces define the interior of the new B-Class. The beautifully crafted interior is the result of studies conducted by Daimler’s Customer Research Centres (CRCs) and the unstinting work of the Mercedes-Benz Advanced Design Studio in Como, Italy.

The Advanced Design Studio is housed at the Villa Salazar which dates back to the 1750s and was once used by the Italian fashion designer Gianni Versace to produce ties and cravats before Mercedes-Benz took it over in February 1998.

The designers can give free rein to their ideas without having to immediately consider series production. The designers use an “appreciation model” to bring their ideas to life and then look for a way to take them through to series production.

At the Daimler Customer Research Centres, there are no predetermined criteria that interviewees must stick to, as with a traditional survey. What these CRCs have found is that the ideal vehicle interior has a good balance between the familiar and the new and progressive. The ideal is to do justice to as many different ideals as possible. In cases where they cannot be reconciled, personalisation is key.

With the new B-Class, for example, Mercedes-Benz makes personalisation easy using three interior packages, as well as providing a broad range of different trim materials and colour choices.

SE versions are enhanced with silver chrome detailing and are fitted as standard with the Sight and Light package of rain-sensing wipers, Headlamp Assist, a three-spoke multi-function steering wheel, air conditioning, an electronic parking brake, ambient lighting, Active Park Assist and an Audio 20 CD/radio player with Bluetooth® and USB interfaces. Unique interior features on Sport models include, among others, Silver Honeycomb trim, heat-insulating dark tinted glass, a reversing camera, Headlamp Assist, brushed stainless steel sports pedals with rubber studs and Artico artificial leather upholstery.

In keeping with other recent Mercedes-Benz model introductions, the new Mercedes-Benz B-Class is fitted with an array of advanced occupant protection features. It is the first car in the world with a radar-based collision warning system, COLLISION PREVENTION ASSIST featuring adaptive Brake Assist. All versions are also fitted with ATTENTION ASSIST, while optional safety features include Lane Keeping Assist and Blind Spot Assist as part of the £785 Lane-Tracking Package Speed Limit Assist, Intelligent Light System (£1,460 on SE, £580 on Sport models) and PRE-SAFE (£345).

The list of Mercedes-Benz luxury comfort and convenience features which has cascaded down to the compact car model is no less impressive, and includes as options COMAND Online (£2,100), a Harmon Kardon Logic7® surround-sound system (£690) and DISTRONIC PLUS (£900).

The two petrol engines in the new Mercedes-Benz B-Class are all-new advanced four-cylinder direct-injection 1.6-litre units, designed for both transverse and longitudinal installation. In the B 180 BlueEFFICIENCY this new 1,595 cc unit – featuring variable camshaft control, reduced internal friction, intelligent oil pump management and highly efficient generator – develops 122 hp at an easy-going 5,000 rpm and 200 Nm of torque constant from 1,250-4,000 rpm for effortlessly relaxed yet spirited performance.

With the six-speed manual gearbox it accelerates from 0-62 mph in 10.4 seconds and has a top speed of 118 mph, yet thanks to the Blue EFFICIENCY measures it is capable of 47.9 mpg, keeping CO2 emissions down to 138-144 g/km, depending on wheel and tyre size. With the 7G-DCT transmission, 0-62 mph acceleration improves to 10.2 seconds, while the top speed and fuel consumption remain the same. The CO2 emissions are 138-145 g/km.

For the B 200 BlueEFFICIENCY, the power increases to 156 hp at 5,300 rpm, with maximum torque of 250 Nm, again remaining constant from 1,250-4,000 rpm. The manual and DCT versions both have a top speed of 137 mph and fuel economy of 45.6 mpg, but while the manual accelerates from 0-62 mph in 8.6 seconds and has CO2 emissions of 144 g/km, the seven-speed DCT is slightly quicker (8.4 seconds) and has CO2 emissions of 145 g/km.

The new 1.8-litre (1,796 cc) third-generation common-rail diesel engine developed for B-Class also comes with a choice of two power options. In the B 180 CDI BlueEFFICIENCY it delivers 109 hp at 3,200-4,600 rpm with 250 Nm of torque consistently between 1,400 and 2,800 rpm. It accelerates from 0-62 mph in 10.9 seconds on the way to a top speed of 118 mph, and delivers combined fuel economy of 64.2mpg with CO2 emissions of 115-121 mpg, depending on the wheels and tyres fitted (DCT: 10.7 seconds, 118 mph, 64.2 mpg, CO2 emissions 116-122 g/km).

The B 200 CDI BlueEFFICIENCY delivers identical fuel economy and CO2 figures to the B 180 CDI, despite increases in engine output to 136 hp at 3,600-4,400 rpm and 300 Nm between 1,600 and 3,000 rpm. This ensures brisk acceleration from 0-62 mph in 9.5 seconds (DCT 9.3 seconds), with a top speed for both versions of 130 mph.

Exterior

The new Mercedes-Benz B-Class launches with a 14-strong model line-up based on four direct-injection turbocharged engines, two transmissions and two trim levels – SE and Sport. Prices start at £21,295 for the B 180 SE manual, rising to £26,160 for the B 200 CDI Sport with the new Mercedes-Benz seven-speed 7G-DCT dual-clutch transmission.

The first of an integrated family of new compact front-wheel-drive cars from Mercedes-Benz, it is the most aerodynamic car in its class, with a Cd of just 0.26. This will fall to an incredible 0.24 with the ECO Technology package due to be introduced soon after launch. Models and prototypes spent around 1,100 hours in the wind tunnel, and more than 275,000 computer hours were invested in digital airflow simulation.

Mercedes-Benz B-Class drivers will have the choice of comprehensively equipped SE or athletic Sport variants. Distinguishing exterior features on SE versions of the new B-Class are 16-inch alloy wheels, projection beam headlamps, round LED daytime running lamps with a chrome surround, a radiator grille with three louvres and a Brilliant Silver chrome surround. The B-Class Sport has 18-inch bi-colour alloy wheels, bi-Xenon headlamps, bar-design LED daytime running lamps with chrome surround, LED rear lights and a radiator grille with chrome trim and two louvres in High-Gloss Black.

Standard equipment includes air-conditioning, a fully integrated ECO start/stop system, an Audio 20 sound system incorporating a 5.8-inch colour display, Bluetooth® interface Headlamp Assist with automatic light activation, ATTENTION ASSIST to alert a potentially tired driver, COLLISION PREVENTION ASSIST to warn of and possibly prevent a collision with a vehicle or stationary object ahead and Active Park Assist.

The patented advanced front wheel arches which channel air over the front wheels feature innovative serrated spoilers that combine with slots in the wheel arches and the aerodynamically optimised alloy wheels to considerably reduce flow losses.

The forecourt-shunning B 200 CDI BlueEFFICIENCY Sport is powered by a new 1.8-litre version of the OM651 third-generation common-rail turbo diesel engine – the first time it has been used in a transverse installation. The manual version delivers combined fuel economy of 64.2 mpg, while CO2 emissions are only 115 g/km.

Petrol versions of the new B-Class – the B180 BlueEFFICIENCY and B 200 BlueEFFICIENCY – benefit from an all-new 1.6-litre direct-injection engine that brings improvements in fuel economy and CO2 emissions of up to 12 per cent compared with those engines in the previous model.

The sandwich-floor concept of the original Mercedes-Benz B-Class has given way to a conventional monocoque body – but with a twist. Mercedes-Benz engineers have devised an Energy Space body concept, which allows the main floor panel to be modified, with a step beginning under the driver’s seat and running rearwards, with just one extra stage in the production process.

At 4,359 mm long and 1,786 mm wide, the new B-Class is 89 mm longer and 11 mm wider than the model it replaces, which endows it with not only a more spacious and more accommodating cabin, but also a more athletic profile. By far the biggest contributor to its more dynamic appearance, however, is the reduction in height of 48 mm, with an increase in headroom.

Interior

The beautifully crafted interior of the new B-Class is the result of studies conducted by Daimler’s Customer Research Centres (CRCs) and the unstinting work of the Mercedes-Benz Advanced Design Studio, housed at the Villa Salazar in Como, Italy.

With all seats in place the B-Class has 486 litres of cargo space, with the option of a height-adjustable load compartment floor. The 60:40 split rear seats fold almost flat to enlarge the luggage area to a maximum of 1,545 litres. The new B-Class can also be ordered with Easy-Vario Plus (£515) sliding and tilting rear seats.

Three large central circular vents sit below a 5.8-inch or 7-inch screen, which seems to float in mid-air. It has an ornamental frame with a galvanised surface, contrasting with the piano black of the front panel, and a TFT colour display. The menus on the screen are operated using the controller in the centre console.

The second-generation Mercedes-Benz B-Class features a robust new passenger cell constructed using 67 per cent high-strength or ultra-high-strength steels. It comprises a new bulkhead and floor, an integral support frame as a deformation element 435 mm in length to dissipate crash energy and load distribution over several planes.

The decision to fit an electronic parking brake as standard in place of a conventional lever, and the gear shifters integrated into the steering wheel with the 7G-DCT transmission, add to the sensation of space and make room for additional storage in the centre console.

What appears to be metal in the new B-Class is metal which has undergone a galvanising process, while the outer rings of the circular vents, the frame of the colour display and the upper shell of the gear lever are in satin-finish polished aluminium.

The B-Class introduces safety features previously unattainable in the compact family car sector to the market. ATTENTION ASSIST and the unique new COLLISION PREVENTION ASSIST are just two of the advanced safety features fitted as standard to every model, joined by seven airbags, ASR Acceleration Skid Control ESP®, and latest generation ABS anti-lock braking system.

Every version of the new B-Class benefits from a suite of BlueEFFICIENCY economy-boosting measures including new highly-efficient direct-injection turbocharged petrol and diesel engines, standard ECO start/stop, intelligent oil feed, water pump and alternator management, low rolling resistance tyres and an adjustable radiator shutter, measures that boost economy by up to 26 per cent over the previous generation model.

In Detail

The new B-Class is the world’s most aerodynamically efficient family car, with a drag co-efficient of Cd 0.26, a figure which will fall to an incredible 0.24 for models with the ECO Technology package due to arrive later in the year.

The aerodynamics of the new Mercedes-Benz B-Class were honed with the help of complex computer calculations and flow simulations. Models and prototypes spent around 1,100 hours in the wind tunnel, and more than 275,000 computer hours were invested in digital airflow simulation. A reduction of just 0.01 in a car’s Cd figure can reduce fuel consumption by up to 6 mpg at a speed of 80 mph.

One aerodynamic trick is worthy of special mention: the patented advanced front wheel arches, which channel air over the front wheels. These innovative serrated spoilers combine with slots in the wheel arches and aerodynamically optimised hubcaps to considerably reduce flow losses.

Equally comprehensive measures ensure a smooth airflow along the underbody. The floor features extensive cladding up to the rear wheel arches, followed by additional cladding around the rear axle. Even the rear silencer has undergone aerodynamic tuning.

The low height of the shoulder on the A-pillar contributes to the car’s outstanding aerodynamic efficiency, and the entire front apron is sealed, while there are also special seals around the headlamps. A large roof spoiler ensures good air separation at the rear, while low-drag door mirrors ensure air is not ‘trapped’ and allowed to stick to the sides of the car to create drag.

Petrol-engined versions feature an adjustable radiator shutter, which adjusts airflow through the engine compartment. When there is no need for a large flow of cooling air, such as when cruising in mild ambient temperatures, the shutter is closed, improving aerodynamics and reducing fuel consumption.

The ECO Technology package, which will be an option on all versions of the B-Class, lowers the ride height, seals the rear window joints and adds cladding to the rear chassis components.

The B-Class is the first Mercedes-Benz to have been designed without a spare wheel well, which saves space and weight and contributes towards the new model’s outstanding efficiency, with fuel consumption reduced by up to 26 per cent.

On SE versions, a tyre pressure warning system advises the driver in the event of a loss of pressure and a TIREFIT system of sealant and an electric pump is provided to effect a temporary repair. Sport models will come with special tyres, which feature full run-flat capability but with softer sidewalls so they do not impact on ride comfort.

Distinguishing exterior features on SE versions of the new B-Class are 16-inch alloy wheels, projection beam headlamps, round LED daytime running lamps with a chrome surround, a radiator grille with three louvres and a Brilliant Silver chrome surround.

The B-Class Sport has 18-inch bi-colour alloy wheels, bi-Xenon headlamps, bar-design LED daytime running lamps with chrome surround, LED rear lights and a radiator grille with chrome trim and two louvres in High-Gloss Black.

The new B-Class is 89 mm longer and 11 mm wider than the model it replaces, but the most significant change in dimensions is the reduction in height of 48 mm, all with the aim of presenting a sleeker, more aerodynamic profile (Cd 0.26). This figure will fall still further, to an amazing 0.24, when the special ECO Technology package that will be optionally available on all versions arrives later in the year.

Yet the B-Class manages the seemingly impossible by providing more headroom, thanks to a reduction in floor height and an 86 mm lower seating position. In response to customer requests, the driving position is now more upright, too. The lower floor of the new Mercedes-Benz B-Class also helps rear legroom, which – with 87 mm of knee clearance – is better than in a standard-wheelbase S-Class.

This sleight of hand is the result of a complete change in the way the B-Class is now constructed. The sandwich-floor layout of the previous model, which placed the engine partly in front of and partly beneath the twin-floor passenger cell, has been replaced by a conventional monocoque body – but with a twist.

To make way for the hybrid, all-electric E-CELL and hydrogen fuel cell F-CELL versions that will be added during the new model’s lifetime, Mercedes-Benz engineers have devised an Energy Space body concept which allows the main floor panel to be modified, with a step beginning under the driver’s seat and running rearwards, with just one extra stage in the production process.

The standard luggage capacity of the new B-Class is 486 litres, while practicality benefits from a 40 mm increase in boot floor width between the wheel arches. The rear sill has been lowered by 5 mm to make loading easier. The rear seats are split 60:40 and fold almost flat, enlarging the luggage capacity to 1,545 litres and allowing loads 1.57 metres long to be carried. A two-tier boot floor is available as part of the Load Compartment Package (£70). This is included in the optional Easy-Vario-Plus system (£515), which provides sliding and reclining rear seats with an armrest containing twin cupholders.

All versions now have an electronic parking brake, freeing more space for storage between the front seats, while those with the optional 7G-DCT (double-clutch transmission) have the gear shifter paddles located within the steering wheel to release even more of the centre console for storage.

This has meant a change in the time-honoured location of the traditional Mercedes-Benz column stalks, which advance from the 8 ‘o’ clock position to 10 ‘o’ clock so that all the controls clustered behind the steering wheel are easy to reach.

Seating options include four-way lumbar support (£165) for the driver and front passenger and a Memory Seat (£815), which allows three preferred driver’s seat and headrest positions to be stored and recalled at the touch of a button. The Mirror Package (£310) also adjusts the door mirrors and automatically lowers the one on the driver’s side when reversing.

Two trim levels are available, each offering an extensive array of comfort, infotainment and safety features as standard. SE versions are trimmed in tone-on-tone black with silver chrome details and have Domburg cloth upholstery in Black or Grey. Standard equipment includes air-conditioning, a fully integrated ECO start/stop system, the Audio 20 sound system incorporating a 5.8-inch colour display, Bluetooth® interface for hands-free telephony and Headlamp Assist with automatic light activation, windscreen wipers with rain sensors and interior ambient lighting.

It also comes with ATTENTION ASSIST to alert a potentially tired driver, COLLISION PREVENTION ASSIST to warn of and possibly prevent a collision with a vehicle or stationary object ahead, Active Park Assist and 16-inch alloy wheels.

Sport models are trimmed in Artico artificial leather and have Silver Honeycomb trim, a Black roof lining and brushed stainless steel pedals with rubber inserts. Standard equipment includes 15 mm lower and firmer sports suspension, DIRECT STEER variable ratio steering, bi-Xenon headlamps with LED daytime running lamps, reversing camera, 18 inch bi-colour alloy wheels, black gloss exterior trim, privacy glass, ATTENTION ASSIST and COLLISION PREVENTION ASSIST.

Optional storage and protection solutions include a rear-mounted folding bicycle rack capable of accommodating up the two cycles (£415), a third cycle kit (£144), a 350-litre Sport rooftop box (£365) or a 450-litre Family rooftop box (£535) and the Zig-zag load sill protection cover (£41) to prevent paintwork scratches while loading large or heavy items.

The interior design story

The beautifully crafted interior of the new B-Class is the result of studies conducted by Daimler’s Customer Research Centres (CRCs) and the unstinting work of the Mercedes-Benz Advanced Design Studio in Como, Italy.

The Advanced Design Studio is housed at the Villa Salazar which dates back to the 1750s and was once used by the Italian fashion designer Gianni Versace to produce ties and cravats before Mercedes-Benz took it over in February 1998. Nearby are the cities of Milan and Turin, home to the Italian furniture and fashion industries, which place a high value on traditional craftsmanship.

These diverse inspirations are reflected in the interior design concepts created by the Como Advanced Design Studio, which trades ideas and even staff with its sister studios in Carlsbad (California), Tokyo, Beijing and back at home base in Sindelfingen just outside Stuttgart. The designers can give free rein to their ideas without having to immediately consider series production. An example is the free-floating, streamlined information screen in the B-Class.

The approach developed in Como by Mercedes-Benz is one reason why the B-Class has achieved a new dimension in quality among compact family cars. The designers use an “appreciation model” to bring their ideas to life and then look for a way to take them through to series production.

At the Daimler Customer Research Centres, interviewers use techniques, which were originally devised by the American psychologist George A. Kelly in the 1950s for research into personality. There are no predetermined criteria that interviewees must stick to, as with a traditional survey.

What these CRCs have found is that the ideal vehicle interior has a good balance between the familiar and the new and progressive. The ideal is not the same for everybody, so the trick is to do justice to as many different ideals as possible. In cases where they cannot be reconciled, personalisation is key. With the new Mercedes-Benz B-Class, for example, Mercedes-Benz makes personalisation easy using three interior packages, as well as providing a broad range of different trim materials and colour choices.

But sight is not the only sense that influences taste. Touch and smell also leave a strong impression on the brain, and rationale is another influence on customer satisfaction. The researchers at the CRC use a model developed in the 1970s by the Japanese customer satisfaction researcher Professor Noriaki Kano. All of this has been applied in the creation of the new B-Class.

The result is a high-quality interior blending emotional design with just the right hint of sportiness. The first thing that strikes you is the large, three-dimensional decorative element spanning the entire dashboard.

Three large central circular vents sit below a 5.8-inch or 7-inch screen, which seems to float in mid-air. It has an ornamental frame with a galvanised surface, contrasting with the piano black of the front panel, and a TFT colour display. The menus on the screen are operated using the controller in the centre console.

The three-spoke steering wheel from the CLS includes a silver chrome insert in the centre spoke, while the four round analogue instruments have hanging needles in the 6 o’clock position.

The decision to fit an electronic parking brake as standard in place of a conventional lever, and the gear shifters integrated into the steering wheel with the 7G-DCT transmission, add to the sensation of space and make room for additional storage in the centre console. The dashboard has a soft-touch matt surface.

With the optional Exclusive package (SE £1,535, Sport £1,055) the dashboard is covered with ARTICO man-made leather. In all versions the large decorative element in the dash is manufactured using IMD (In-Mould-Decoration) technology. Printed foils are inserted into the mould which is then filled with thermosoftening plastic. This results in moulded parts with an outstanding finish and a high-quality appearance. In Sport versions, the decorative element is printed on both sides, adding depth to the pattern.

And what appears to be metal in the new B-Class is metal which has undergone a galvanising process, while the outer rings of the circular vents, the frame of the colour display and the upper shell of the gear lever are in satin-finish polished aluminium.

The high-quality impression is reinforced at night by the ambient interior lighting through a fibre-optic cable, which bathes the lower half of the cabin in a soft amber glow. Ambient lighting also includes footwell lighting in the front as well as illuminated door handle recesses.

Design

The new Mercedes-Benz B-Class is a sleeker and sportier-looking car than the model it replaces. The first of an integrated family of new compact front-wheel-drive cars from Mercedes-Benz, it is the most aerodynamic car in its class, with a Cd of just 0.26. This will fall to an incredible 0.24 with the ECO Technology package due to be introduced soon after launch. The aerodynamic excellence of the new B-Class is a major contributor to its outstanding fuel-efficiency and low CO2 emissions.

The fundamental principle behind the design of the new B-Class is that it should provide five-seater family-car space within a rakish and aerodynamically efficient body shell that will be able to accommodate hybrid, battery-electric (E-CELL) and hydrogen fuel cell (F-CELL) powertrains in the not-too-distant future.

To make this possible there has been a complete change of mindset about the body construction of the car. The sandwich-floor concept of the original Mercedes-Benz B-Class has given way to a conventional monocoque body – but with a twist. Mercedes-Benz engineers have devised an Energy Space body concept, which allows the main floor panel to be modified, with a step beginning under the driver’s seat and running rearwards, with just one extra stage in the production process.

At 4,359 mm long and 1,786 mm wide, the new B-Class is 89 mm longer and 11 mm wider than the model it replaces, which endows it with not only a more spacious and more accommodating cabin, but also a more athletic profile. By far the biggest contributor to its more dynamic appearance, however, is the reduction in height of 48 mm, without any compromises in headroom, which has actually increased.

This has been achieved by a radical shift away from the sandwich floor layout of the previous generation B-Class. This lowering the floor and the position of the seats is in direct response to customer preferences for a more saloon-like driving position than in the outgoing B-Class range.

The increased width is emphasised at the front by a broad grille and lower air intake which opens out into a trapezoid shape towards round LED daytime running lights in SE versions and bar-type LED daytime running lights on the Sport model. The radiator grille on the SE has three louvres and a Brilliant Silver chrome surround, while that on the Sport has chrome trim and two louvres in High-Gloss Black. Sport models also feature Bi-Xenon headlamps. The Mercedes-Benz Intelligent Light System, which automatically adjusts the beam pattern to suit the speed of the car and the kind of road it is being driven on, is an option (£1,460 on the SE and £580 for the Sport).

The outstanding aerodynamics of the new B-Class are best appreciated from the side, where the bonnet line apparently flows seamlessly into the A-pillars and on to the sweeping roof, which ends with a striking spoiler. The roof features a “Pagoda Roof”-style swage line, which seems to stretch the car’s length. The side windows have no visible frames, adding to the sporty appearance, which is further emphasised by pronounced wheel arches offset by dynamic feature lines.

The bottom edge of the bodywork finishes in dynamic side skirts, while sharp looking 16-inch (SE) or 18-inch (Sport) alloy wheels add a final touch of sportiness to the overall appearance. The B-Class Sport also rides 15mm closer to the ground than the SE.

The aerodynamics of the new Mercedes-Benz B-Class were honed with the help of complex computer calculations and flow simulations. Models and prototypes spent around 1,100 hours in the wind tunnel, and more than 275,000 computer hours were invested in digital airflow simulation. A reduction of just 0.01 in a car’s Cd figure can improve fuel consumption by up to 6 mpg at a speed of 80 mph.

One aerodynamic trick is worthy of special mention: the patented advanced front wheel arches, which channel air over the front wheels. These innovative serrated spoilers combine with slots in the wheel arches and aerodynamically optimised hubcaps to considerably reduce flow losses.

Equally comprehensive measures ensure a smooth airflow along the underbody. The floor features extensive cladding up to the rear wheel arches, followed by additional cladding around the rear axle. Even the rear silencer has undergone aerodynamic tuning.

The ECO Technology package, which will be an option on all versions of the B-Class lowers the ride height, seals the rear window joints and adds cladding to the rear chassis components.

The B-Class is the first Mercedes-Benz to have been designed without a spare wheel well, which saves space and weight. On SE versions, a tyre pressure warning system advises the driver in the event of a loss of pressure and a TIREFIT system of sealant and an electric pump is provided to effect a temporary repair. Sport models will come with special tyres, which feature full run-flat capability but with softer sidewalls so they do not impact on ride comfort.

The beautifully crafted interior of the new B-Class is the result of studies conducted by Daimler’s Customer Research Centres (CRCs) and the unstinting work of the Mercedes-Benz Advanced Design Studio in Como, Italy. The result is a high-quality interior blending emotional design with just the right hint of sportiness.

It features three large central circular vents sit below a 5.8-inch or 7-inch screen, which seems to float in mid-air, framed by a galvanised surface. The three-spoke steering wheel from the CLS includes a silver chrome insert in the centre spoke.

All versions now have an electronic parking brake, freeing more space for storage between the front seats, while those with the optional 7G-DCT (double-clutch transmission) have the gear shifter paddles located within the steering wheel to release even more of the centre console for storage. This has meant a change in the time-honoured location of the traditional Mercedes-Benz column stalks, which advance from the 8 ‘o’ clock position to 10 ‘o’ clock so that all the controls clustered behind the steering wheel are easy to reach.

The dashboard has a soft-touch matt surface. With the optional Exclusive package (SE £1,535, Sport £1,055) the dashboard is covered with ARTICO man-made leather. And what appears to be metal in the new B-Class is metal which has undergone a galvanising process, while the outer rings of the circular vents, the frame of the colour display and the upper shell of the gear lever are in satin-finish polished aluminium.

The high-quality impression is reinforced at night by the ambient interior lighting through a fibre-optic cable which bathes the lower half of the cabin in a soft amber glow. Ambient lighting also includes footwell lighting in the front as well as illuminated door handle recesses.

Two trim levels are available, each with their own individual trim treatments. SE versions are in tone-on-tone black with silver chrome details and have Domburg cloth upholstery in Black or Grey. Sport models are trimmed in Artico artificial leather and have Silver Honeycomb trim, a Black roof lining and brushed stainless steel pedals with rubber inserts. Externally, they’re visually distinguished by their 18-inch bi-colour alloy wheels and black gloss exterior trim.

“High-quality materials and finely structured surfaces, stylish details, precision workmanship and a new spaciousness – the interior of the B-Class defines a whole new benchmark in the compact segment,” says Professor Gorden Wagener, Head of Design, Mercedes-Benz Cars. “Many features have been the reserve of higher classes of vehicle to date and embody Mercedes-Benz’s special understanding of quality and aesthetics.”

Technology

With world-exclusive safety features, class-leading aerodynamics, Mercedes-Benz firsts in the form of new direct-injection engines and a seven-speed dual-clutch automatic transmission, and new architecture designed to accommodate alternative powertrains in future, every millimetre of the compact new Mercedes-Benz B-Class is packed with advanced Mercedes-Benz technology.

In the areas of safety and efficiency it makes significant advances in the compact family car class thanks to technologies, which have cascaded down from the company’s larger saloons. Some of the technology which features on the new four-cylinder engines was developed for Mercedes-Benz V6 and V8 units, for example, while the list of standard and optional safety features is a match for that which is available on the company’s most prestigious saloons.

The B-Class is also available with the latest comfort, luxury and convenience features from Mercedes-Benz, and during its lifetime it will become the company’s first car to be commercially available with a hydrogen fuel cell (F-CELL) powertrain thanks to the flexible and intelligent new architecture that the car is based on. In fact, the roster of features available on the B-Class is so comprehensive that it reads almost like a resumé of Mercedes-Benz technology at the start of 2012.

Aerodynamics

The new B-Class is the world’s most aerodynamically efficient compact family car. It has a co-efficient of drag (Cd) of 0.26 – a highly impressive figure for a car with an estate-like rear, but incredibly this will fall still further to 0.24 when the optional ECO Technology package becomes available later this year. The aerodynamics were honed with the help of complex computer calculations and flow simulations. Models and prototypes spent around 1,100 hours in the wind tunnel, and more than 275,000 computer hours were invested in digital airflow simulation.

One aerodynamic feature worthy of special mention is the patented advanced front wheel arches which channel air over the front wheels. These innovative serrated spoilers combine with slots in the wheel arches and aerodynamically optimised hubcaps to considerably reduce flow losses. Equally comprehensive measures ensure a smooth airflow along the underbody. The floor features extensive cladding up to the rear wheel arches, followed by additional cladding around the rear axle. Even the rear silencer has undergone aerodynamic tuning. The ECO Technology package which will be an option on all versions of the B-Class lowers the ride height, seals the rear window joints and adds cladding to the rear chassis components.

Active Park Assist (£705 option)

The new B-Class is available with Active Park Assist with Parktronic ultrasound sensors. At speeds below 20mph this is able to assess parking spaces to see if the car will fit in. Once a suitable space has been found and the car is in reverse, Active Park Assist steers the car in while the driver works the clutch, brakes and accelerator. Active Park Assist is standard on SE versions of the new B-Class and optional on Sport models, and in addition, all Sport models are fitted with a reversing camera as standard.

ADAPTIVE BRAKE

Every version of the Mercedes-Benz B-Class is fitted with ADAPTIVE BRAKE to minimise stopping distances in emergencies. If the driver abruptly releases the accelerator pedal – the first reaction in a potential emergency – ADAPTIVE BRAKE primes the brake pads so that they come into light contact with the brake discs. Should emergency braking then be required the necessary braking pressure is achieved instantly. During wet weather it systematically applies brake contact to dry the brake discs. Hill Start Assist is also standard to ensure the new B-Class always pulls away smoothly, even on the steepest uphill gradient. It also keeps the car stationary whenever it comes to rest without the driver having to keep a foot on the brake pedal.

ATTENTION ASSIST

The innovative system developed by Mercedes-Benz to monitor driver behaviour and warn of signs of tiredness is standard in the new B-Class. It is primarily based on steering wheel movements, since this is the first thing that becomes erratic when a driver is getting tired. The system monitors more than 70 parameters, which are then assessed for signs of drowsiness.

During the first few minutes of every journey, ATTENTION ASSIST draws up a bespoke driver profile which is then compared with on-going data as well as the prevailing driving conditions. If ATTENTION ASSIST detects signs of drowsiness it issues an audible warning and flashes up a visual warning in the instrument cluster.

BlueEFFICIENCY

Every version of the new B-Class benefits from a suite of BlueEFFICIENCY economy-boosting measures which combine to ensure the new engines are up to an incredible 26 per cent more economical than those in the previous model. BlueEFFICIENCY measures on the new B-Class include new highly-efficient direct-injection turbocharged petrol and diesel engine, ECO start/stop as standard, intelligent alternator management to convert braking energy into electrical energy, intelligent management of the oil feed and water pump, a display to encourage more economical driving, low rolling resistance tyres and an adjustable radiator shutter.

COLLISION PREVENTION ASSIST

The new Mercedes-Benz B-Class is fitted as standard with COLLISION PREVENTION ASSIST, a world-first feature exclusive to Mercedes-Benz. This is a radar-based system which can reduce the risk of nose-to-tail collisions, or minimise their effects, in conjunction with ADAPTIVE BRAKE. COLLISION PREVENTION ASSIST alerts a distracted driver through visual and acoustic warnings if it senses an accident is likely to happen.

It also primes the Brake Assist function to ensure maximum stopping power as soon as the driver touches the brake pedal. Unlike some systems, which work only at urban speeds, COLLISION PREVENTION ASSIST functions at any speed above 20 mph. Mercedes-Benz safety experts believe COLLISION PREVENTION ASSIST can prevent around 20 per cent of all nose-to-tail collisions and reduce the severity of them in another 25 per cent of cases.

COMAND Online with Media Interface (£2,100)

As an option the new B-Class can be ordered with COMAND Online, which allows the car to be connected to the internet when stationary through a suitably enabled mobile telephone. COMAND Online with Media Interface is the hub for a vast range of communications, entertainment and navigation services that are possible with the new B-Class. It combines in-car internet access with a wide range of entertainment features and a hard-drive navigation system.

The system includes 10GB of storage space for building a music library, speed-sensitive volume adjustment of the audio system and a DVD drive that plays CDs, MP3s or video and audio DVDs. It also allows a number of external devices and storage media to be connected via a USB port, a Media Interface, an SD card slot or Bluetooth®. With an internet-enabled mobile phone, owners can access the internet when the car is stationary, and have access to Mercedes-Benz online services. Integrated Mercedes-Benz apps include Google™ Local Search and Weather and the option of downloading a route, which has been set up on a home computer through Google™ Maps.

Direct injection and turbocharging

Every version of the new B-Class is powered by a direct-injection turbocharged engine, helping significantly towards improvements of 26 per cent in fuel economy and emissions compared to the previous model. The two petrol engines are all-new advanced four-cylinder 1.6-litre units, designed for both transverse and longitudinal installation. The diesels are new 1.8-litre units developed from the 2.2-litre OM651 fourth-generation four-cylinder unit premiered in 2008 and featuring third-generation common-rail technology.

Energy Space architecture

The new B-Class is built around Energy Space body architecture in place of the sandwich floor concept of the previous model. This allows the seating positions to be lowered in response to customer requests while still providing greater headroom. It will also allow the main floor panel to be modified, with a step beginning under the driver’s seat and running rearwards, with just one extra stage in the production process. This will make it possible to accommodate hybrid, battery-electric (E-CELL) and hydrogen fuel cell (F-CELL) powertrains which Mercedes-Benz has pledged to introduce in the not-too-distant future.

ECO start/stop

All versions of the new B-Class are fitted with ECO start/stop technology, which ensures that no fuel is used and no emissions are created when the car is stationary in traffic. The system seamlessly stops the engine when the car is at rest and swiftly restarts it the moment the driver wishes to pull away. In manual versions the engine switches off as soon as the driver applies the brakes, shifts the transmission lever into neutral and releases the clutch. The engine restarts as soon as the driver depresses the clutch.

With the new 7G-DCT (dual-clutch automatic transmission), the ECO start/stop function deactivates the engine as soon as the vehicle is motionless and the driver depresses the brake pedal. The engine restarts automatically when the driver’s foot is removed from the brake pedal or the accelerator pedal is pressed. The system includes a number of safety defaults to ensure it can only function under the driver’s control.

7G-DCT automatic transmission (£1,450 option)

A new type of Mercedes-Benz gearbox makes its debut in the new Benz B-Class – the 7G-DCT (dual-clutch automatic transmission). It is optionally available on every model and delivers the comfort and convenience of a full automatic system with the fuel economy of a manual. It incorporates three shift programmes – ECONOMY, SPORT and MANUAL. In ECONOMY and SPORT gearshifts are fully automatic, while MANUAL mode hands full control to the driver. The two ‘wet’ multi-disc clutches running in an oil bath are activated and the gears shifted automatically without any interruption in power flow.

One of the clutches operates during selection of the ‘odd’ gears and the other works for the ‘even’ gears. That means the next gear is always primed ready to come into operation instantaneously and smoothly as needed, whether accelerating or braking. Thanks to its seven gears it allows a wide spread of ratios.

Intelligent Light System (£1,460 for SE and £580 for Sport models)

The new Mercedes-Benz B-Class is optionally available with the Mercedes-Benz Intelligent Light System incorporating bi-Xenon headlights with LED daytime running lights, Adaptive High Beam Assist and cornering light function. It features five light functions – country mode, motorway mode, enhanced foglamps, active light function and cornering light function -designed specifically for differing driving situations or weather conditions. Low beam is replaced by country road mode, which illuminates the driver’s side of the road more brightly than the centre.

At speeds above 55 mph, motorway mode takes over, increasing the driver’s range of vision by up to 60 per cent. The enhanced foglamps are activated at speeds below 40 mph as soon as the rear foglamp is switched on, while the active light and cornering light functions are switched on automatically, depending on the steering angle, rate of turn and vehicle speed. The Intelligent Light System includes Adaptive High-beam Assist, which constantly and automatically adjusts the range of the headlamps based on the distance of oncoming vehicles or those in front of the car. The Mercedes-Benz system uses graduated steps between ‘dipped’ and main beam rather than a sudden switching between two modes.

Lane-Tracking Package (£785)

The new B-Class can be ordered with the Mercedes-Benz Lane Tracking Package designed to prevent owners from straying into the path of other cars when changing lanes or should they become distracted while at the wheel. It consists of Lane Keeping Assist and Blind Spot Assist. Lane-Keeping Assist reads the lane markings on the road and, if the car crosses them unintentionally, it alerts the driver by gently vibrating the steering wheel. Blind Spot Assist uses two radar sensors to detect a vehicle approaching from behind that the driver may not have seen. If the B-Class driver then attempts to pull out to overtake, it issues visual warnings in the door mirrors and an audible warning within the car.

PRE-SAFE® (£345)

The Mercedes-Benz anticipatory safety system PRE-SAFE® is available as an option on the new B-Class Using the ESP® Electronic Stability Programme sensors, it can recognise potentially dangerous situations and transmit the information to the car’s electronic control units within milliseconds so that the seat belts and airbags deploy with maximum effect in the event of a collision. It also closes any open windows and the sunroof if fitted and moves the front passenger’s seat to the safest position if the car has been ordered with the Memory Pack.

Chassis

For the new B-Class, the sandwich-floor layout of the previous model, which placed the engine partly in front of and partly beneath the twin-floor passenger cell, has been replaced by a conventional monocoque body – but with a twist. To make way for the hybrid, all-electric E-CELL and hydrogen fuel cell F-CELL versions that will be added during the new model’s lifetime, Mercedes-Benz engineers have devised an Energy Space body concept which allows the main floor panel to be modified, with a step beginning under the driver’s seat and running rearwards, with just one extra stage in the production process.

The new B-Class builds on the impeccable Mercedes Benz safety reputation with a structural design and a body-in-white, which features 67 per cent of high-strength or ultra-high-strength steels.

The safety credentials of the new Mercedes-Benz B-Class are underscored by a new bulkhead and floor, an integral support frame as a deformation element, a length of 435 mm over which to dissipate crash energy and load distribution over several planes. Altogether, three longitudinal planes allow impact energy to be reduced in a controlled manner.

The integral support frame serves as an attachment point for the front axle and steering assembly as well as the torque support for the transversely mounted engine and gearbox. It consists of several steel plates and a hydroformed tube, and is connected by two aluminium struts to the radiator mount, which is also made from aluminium.

To ensure that the doors will open even after a high-speed impact, there is a plastic crash wedge at the rear of each front wheel arch to prevent the wheel from sliding beneath the door.

A special feature known as skate runners discharges frontal impact forces into the floor, which features four straight longitudinal members. The passenger cell is protected against side impact by rigid structures which include the so-called pole support, fitted diagonally between the central tunnel and the floor sidewalls. This is intended to prevent the floor being torn open even in the event of a side impact with a tree.

High-strength steels are used in the upper part of the B-pillar to minimise intrusion, but the lower part of the pillar is made from softer steels to dissipate crash energy in a more controlled way. The B-pillars also house what Mercedes-Benz engineers have christened ‘vampire’s teeth’ – small tooth-like recesses which prevent the seat-belt retractor from causing the kind of crack that might affect the body’s structural integrity in a crash.

For the alternative powertrain versions of the B-Class, which Mercedes-Benz will introduce in the not-too-distant future, a sandwich-floor element will be introduced into the rear of the body structure by adding just one extra stage into the assembly process.

Steering

The redesigned electro-mechanical steering system of the new B-Class places the electric motor, which provides servo assistance directly on the steering gear. Electro-mechanical power steering makes a significant contribution to the much-improved efficiency of the latest model because steering assistance is provided only when the car is actually turning. With a turning circle of 11 metres, the new B-Class is particularly nimble.

The new steering system also permits various assistance functions which are activated by the ESP® control unit. It can compensate for the effect of crosswinds and road camber, mitigate against the torque-steer effect found in some front-wheel-drive cars, keep the car on a straight course when braking on road surfaces with different levels of grip left to right and counter-steer should the car develop oversteer. It also makes the standard-fit Active Park Assist possible.

Active Park Assist measures potential parking spaces through two ultrasonic sensors on the front bumper. If the car will fit the system operates the electro-mechanical power steering while the driver works the accelerator and brake.

Sport versions come as standard with Mercedes-Benz’s new Direct-Steer system, which provides variable hydraulic assistance that reduces as speed increases and adds a variable ratio that changes according to the steering angle.

The ratio is indirect when steering straight ahead for exceptional straight-line stability, but increases rapidly once a five degree steering angle is reached, becoming extremely direct from a steering angle of just 100 degrees. This results in the driver having to make only relatively small steering movements when manoeuvring the car both in confined areas or when negotiating a series of tight corners. This enhances handling and agility substantially along with the lower and firmer sports suspension and the large 18-inch alloy wheels and low-profile tyres on Sports models.

The variable ratio is achieved by using a steering rack with different profiled teeth. By adopting a mechanical base, the engineers have been able to create a low-weight set-up with a low susceptibility to faults..

Brakes

All versions of the new B-Class have a powerful all-disc braking system, with the rear calipers and brake boosters fashioned from aluminium. It is the first compact Mercedes-Benz to be fitted with the HOLD function from the company’s larger models. A slightly firmer push of the brake pedal ensures the car is held without the driver having to maintain pressure on the pedal.

It disengages as soon as the driver touches the accelerator. Manual versions also have the Hill Hold function which ensures the car can not roll backwards when setting off on uphill gradients by momentarily maintaining braking pressure while the driver moves his or her right foot to the accelerator pedal.

The Hill Hold function is incorporated into the standard-fit ADAPTIVE BRAKE feature, which works in conjunction with the Anti-lock Brakes (ABS) to enhance the dynamic safety of the Mercedes-Benz B-Class in critical driving situations. ADAPTIVE BRAKE is also linked to the ASR acceleration skid control and GMR active yaw control units.

Should the driver abruptly lift off the accelerator pedal – the first reaction in a potential emergency – ADAPTIVE BRAKE primes the brake pads so that they come into light contact with the brake discs. If emergency braking proves to be necessary, pressure can therefore be achieved instantly. During wet weather the system dries the brake discs by maintaining gentle pressure between brake pads and discs for enhanced performance.

For the first time an electronic parking brake is standard on the B-Class, helping to free more storage space between the front seats. In models fitted with the 7G-DCT transmission (£1,450 option) it self-releases as the car moves away as long as the driver’s seat belt is fastened. If activated at speeds of more than 2 mph it also serves as an emergency brake through the ESP® system’s hydraulic unit.

Suspension

With a lower centre of gravity, a redesigned MacPherson strut front suspension system and a new four-link rear axle, upgraded ESP® Electronic Stability Programme plus the choice of two different spring and damper settings, the new B-Class is a more agile and responsive car than the one it replaces while maintaining the comfort levels and refinement that are an essential feature of any Mercedes-Benz family car.

The new four-link rear axle features three control arms and one trailing arm per wheel so that longitudinal and lateral forces are absorbed virtually independently of each other. The wheel carriers and spring links are made of aluminium to reduce unsprung weight.

Sport versions of the new B-Class are fitted with sports suspension, consisting of a 15 mm lower ride height and firmer springs and dampers. Alloy wheels of 18 inches in diameter replace the 16-inch alloys on SE models. This combination ensures excellent body control and roadholding, while the Direct Steer system that is also standard on Sport versions adds an extra veneer of agility and precision to the driving characteristics.

The new B-Class also features the latest ESP® Electronic Stability Programme. This includes Torque Vectoring Brake, which helps to control oversteer in fast cornering by applying slight brake pressure to the outer rear wheel. The latest ESP® system intervenes more gently so that sporty and experienced drivers can get maximum enjoyment out of the car while being certain that they and their passengers are offered full protection in the event of a potentially critical scenario.

B 180 BlueEFFICIENCY and B 200 BlueEFFICIENCY

Petrol versions of the new Mercedes-Benz B-Class are powered by a brand new (M270) 1.6-litre 1,595 cc direct-injection turbocharged engine that has been designed so that it can be mounted either transversely, as in the case of the B-Class, or longitudinally. It works in conjunction with the Mercedes-Benz ECO start/stop function.

The specification reads almost like a catalogue of the arts of modern petrol engine construction – all-aluminium, twin chain-driven overhead camshafts, third-generation direct petrol injection, forced induction via a turbocharger and spray-guided combustion based on that in the Mercedes-Benz BlueDIRECT V6 and V8 engines. Despite being turbocharged, the engine is able tom operate on a high compression ratio of 10.3:1.

Completely new piezo-electric injectors deliver up to five injections per power stroke at a pressure that can be as high as 200 bar, while multi-spark ignition ensures the most efficient combustion of the fuel-air mixture. Thanks to continuous adjustment of the inlet and exhaust camshafts, the system is ideal for scavenging. This process, which ensures that cold air being drawn into the engine, drives the hot exhaust gases in the cylinder into the exhaust manifold. This increased mass flow helps the engine to respond more quickly at low revs, eliminating turbo lag.

Both versions of the engine, which delivers 122 hp in the B 180 and 156 hp for the B 200, attain maximum torque at only 1,250 rpm and maintain it at a constant level to 4,000 rpm. The peak torque figures are 200 Nm and 250 Nm respectively.

The engine maintains its efficiency even under high load as there is no need to enrich the mixture to cool the cylinder head up to a speed of 125 mph. A two-piece water jacket with optimum cross-flow cooling and fine cooling ducts measuring only 3 mm conveys coolant to the critical areas. Meanwhile a new thermal management system ensures that no coolant flows through the engine during the warm-up phase, helping the engine attain ideal operating temperature faster.

Mercedes-Benz was the first manufacturer to employ direct petrol injection in a four-stroke series production engine as long ago as the mid-1950s for the legendary 300 SL ‘Gullwing’ Coupe.

B 180 CDI BlueEFFICIENCY and B 200 CDI BlueEFFICIENCY

The diesel engines in the new B-Class are further developments of the OM651 fourth-generation four-cylinder unit premiered in 2008. This new variant has a capacity of 1.8 litres (1,796 cc), achieved by shortening the piston stroke by 16 mm from 99 mm to 83 m, and has a cast-iron block beneath an aluminium cylinder head.

Compared with the larger-capacity version used in rear-wheel-drive models from Mercedes-Benz, it has a modified belt drive and air ducting and a new turbocharger mounting to suit transverse installation in the Mercedes-Benz B-Class. Cylinder spacing of 94 mm and spur-gear camshaft drive make it particularly compact for transverse mounting.

Third-generation common-rail technology, with the rail pressure increased to 1,800 bar and a maximum ignition pressure of 200 bar, allows both versions of the engine to attain their high specific outputs – 109 hp for the B 180 CDI and 136 hp in the B 200 CDI. A two-piece water jacket in the cylinder head provides optimum cooling around the combustion chamber plate and contributes towards the high specific power outputs.

Fuel efficiency benefits from a number of painstakingly detailed measures: the oil injector nozzles and the water pump become active only as necessary, reducing energy drain on the engine, and the oil pump reduces oil flow in a controlled manner. The two Lanchester balancer shafts at the bottom of the engine block run in low-friction roller bearings rather than conventional plain bearings and the markedly longer connecting rods both help reduce friction and thus help to improve fuel economy.

The Lanchester balancer shafts contribute towards the smooth-running characteristics of both engines by compensating for the second-order forces which are inherent in an in-line four-cylinder unit. Refinement is further improved by a dual-mass flywheel specifically designed to isolate crankshaft vibrations in an engine developing high torque at low revolutions.

ECO start/stop

All versions of the new Mercedes-Benz B-Class are fitted with intelligent and extremely efficient ECO start/stop technology which ensures that no fuel is used and no emissions are created when the car is stationary in traffic. The system seamlessly stops the engine when the car is at rest and swiftly restarts it the moment the driver wishes to pull away. It requires the minimum of intervention by the driver.

In manual versions the engine switches off as soon as the driver applies the brakes, shifts the transmission lever into neutral and releases the clutch. The engine restarts as soon as the driver depresses the clutch.

With the new 7G-DCT (dual-clutch automatic transmission), the ECO start/stop function deactivates the engine as soon as the vehicle is motionless and the driver depresses the brake pedal. The engine restarts automatically when the driver’s foot is removed from the brake pedal or the accelerator pedal is pressed.

The system includes a number of safety defaults to ensure it can only function under the driver’s control. Naturally, it will only work once the car is stationary. In manual versions, the brakes must be applied, the transmission must be in neutral and the clutch pedal must be released. In those with the 7G-DCT gearbox, the shift lever must be in Drive or Neutral. In both cases, there must be no steering wheel movement, the doors and bonnet must be closed and the driver’s seat-belt must be fastened. The driver’s foot must be on the brake pedal or the HOLD function must be active, too. And the engine will automatically restart if it detects a vehicle-related precondition – such as the air conditioning working hard in a hot climate.

The ECO start/stop system employs a sensor which monitors the angle of the crankshaft and the position of the individual cylinders. When restarting the engine, the sensor determines which cylinder is in the best position for initial ignition for smooth and instantaneous start-up.

Thanks to direct-start technology, the Mercedes-Benz-developed system operates spontaneously and with little noise. Fuel is injected directly and ignited during the piston’s compression stroke, allowing the engine to be started with little assistance from the starter. Advanced software management ensures the ECO start/stop system operates only when the engine and cabin have both reached the correct temperature. The driver can also independently switch the system off.

To handle the requirements of the ECO start/stop system, the starter motor has undergone thorough modification. It can cope with eight times as many starting procedures as before to ensure that even in continuous urban driving involving frequent auto-starting, it will last the car’s lifetime. A second battery supports the on-board electrical system.

New 7G-DCT (dual-clutch automatic transmission)

A new type of Mercedes-Benz gearbox makes its debut in the new B-Class – the 7G-DCT (dual-clutch automatic transmission). It is optionally available on every model (£1,450) and delivers the comfort and convenience of a full automatic system with the fuel economy of a manual. Thanks to the three shift programmes it allows, drivers are also able to exercise full manual control through paddles behind the steering wheel for sporty driving, with gear changes taking place far faster than even the most skilled driver can execute with a manual transmission.

The three shift programmes are ECONOMY, SPORT and MANUAL. In ECONOMY, gearshifts are fully automatic, but take place at the lowest possible engine revolutions to promote a particularly fuel-efficient driving style. In SPORT the gear changes are also fully automatic, but are completed in a shorter time. In both modes the driver can intervene to make a manual shift at any time using the steering wheel paddles. The transmission reverts to automatic mode if no further manual gear changes are made after 10 seconds, or after a longer delay when driving downhill or on winding roads. MANUAL mode hands full control to the driver, and the shifts take place even faster than in SPORT.

The two ‘wet’ multi-disc clutches running in an oil bath are ideally suited to engines with high torque outputs like the direct-injection turbocharged units fitted to every new B-Class. The clutches are activated and the gears shifted automatically without any interruption in power flow, which makes this type of transmission both dynamic and comfortable.

Thanks to its seven gears it allows a wide spread of ratios, including high top gears for quiet, economical cruising, and is vastly more fuel-efficient than the CVT continuously variable transmission available in the previous Mercedes-Benz B-Class. The new B 200 CDI with the 7G-DCT transmission achieves combined fuel economy of 64.2 mpg compared with the 50.4 mpg of the previous B 200 CDI with CVT, for example.

The Mercedes-Benz 7G-DCT is more compact and lighter than other comparable transmissions, and is operated by a selector lever and shift paddles integrated into the steering wheel, a first for a compact family car

One of the clutches operates during selection of the ‘odd’ gears and the other works for the ‘even’ gears. That means the next gear is always primed ready to come into operation instantaneously and smoothly as needed, whether accelerating or braking.

Cruise Control and the Speedtronic variable speed limiter are included with the 7G-DCT automatic transmission, along with the brake HOLD function. All the driver needs to do is push the brake pedal slightly more firmly than usual and the car will remain held without the need to keep pressing the pedal down. The HOLD function also restrains the car momentarily when setting off on steep gradients to prevent it rolling backwards.

Six-speed manual transmission

The default gearbox on the new Mercedes-Benz B-Class is a new six-speed manual transmission developed in conjunction with the 7G-DCT. The two transmissions share a large number of components and are produced in the same Hedelfingen plant.

The six-speed manual transmission is also very compact and light, and designed for satisfyingly quick and positive shifting. For example, lightweight cast-aluminium shift forks are installed on anti-friction bearings on the shift rods to reduce the effort needed for gear changing. Like the 7G-DCT, it features a wide spread of ratios so that the new B-Class is just as capable of setting off on a steep slope with a trailer in tow as it is at cruising quietly and economically on the motorway.

Safety

The new B-Class from Mercedes-Benz takes a holistic approach to safety, which offers occupants a standard of protection that belies its compact exterior dimensions. It brings safety features previously unattainable in the compact family car sector to the market. ATTENTION ASSIST and the unique new COLLISION PREVENTION ASSIST are just two of the advanced safety features fitted as standard to every model. Together, they will alert a driver who unknowingly is getting tired to take a break and can prevent an impact, or at the very worst minimise the consequences of one.

But the approach to safety with the new B-Class does not stop there. The full raft of safety features developed for other Mercedes-Benz passenger cars is available in the company’s new compact family car. They include:

• PRE-SAFE® anticipatory crash protection system (£345)
• DISTONIC PLUS adaptive cruise control (£900, with 7G-DGT 7-speed automatic transmission only)
• Intelligent Light System, which adapts its beam pattern according to where and how the car is being driven (£1,460 on SE and £580 on Sport models)
• Lane-Keeping Assist/Blind Spot Assist to prevent the driver straying into the path of an overtaking car or inadvertently crossing lanes while distracted (£785)

These are merely the headline acts in a comprehensive approach to crash prevention and occupant protection, which begins with the robust new passenger cell developed for the second-generation Mercedes-Benz B-Class. This is constructed using 67 per cent high-strength or ultra-high-strength steels and features a new bulkhead and floor, an integral support frame as a deformation element, a length of 435 mm over which to dissipate crash energy and load distribution over several planes. Altogether, three longitudinal planes allow impact energy to be reduced in a controlled manner. The aim of the new B-Class safety engineers was to avoid accidents from happening wherever possible, but to ensure unrivalled protection should the worst happen.

Seven airbags are standard in every B-Class. These consist of dual-stage front airbags, which are triggered according to the severity of the impact, window bags, pelvis bags for the driver and front passenger and a driver’s side kneebag. Side bags for rear seat occupants are available as an option (£395).

The steering column deforms by up to 100 mm as soon as the driver’s head comes into contact with the airbag, considerably reducing the chances of serious injury, while the head restraints for the driver and front passenger are new developments of the Mercedes-Benz NECK-PRO system designed to minimise the risk of whiplash injuries. They incorporate a button which has to be pushed if either occupant wants to increase the distance between head and restraint, but allow the restraint to be moved closer to the head freely. Belt tensioners and force limiters are fitted to the two front and two outer rear seats, and there are ISOFIX child-seat mounting points in the rear.

ATTENTION ASSIST, the innovative system developed by Mercedes-Benz to monitor driver behaviour and warn of signs of tiredness, is fitted as standard. It is primarily based on steering wheel movements, since this is the first thing that becomes erratic when a driver is getting tired. The system monitors more than 70 parameters, which are then assessed for signs of drowsiness.

Continuous monitoring is crucial in detecting the gradual transition from alertness to drowsiness. In this way, the driver is given plenty of warning that it would be sensible to take a break. During the first few minutes of every journey, ATTENTION ASSIST draws up a bespoke driver profile which is then compared with on-going data as well as the prevailing driving conditions.

If ATTENTION ASSIST detects signs of drowsiness through its highly sensitive steering angle sensors, it issues an audible warning and flashes up a visual warning in the instrument cluster: ATTENTION ASSIST Take a Break! The system is active at speeds of between 50 and 110 mph.

COLLISION PREVENTION ASSIST

The new B-Class is also fitted as standard with a world first in the compact family car class in the form of COLLISION PREVENTION ASSIST. This is a radar-based system which can reduce the risk of nose-to-tail collisions, or minimise their effects, in conjunction with the standard ADAPTIVE BRAKE feature.

COLLISION PREVENTION ASSIST alerts a distracted driver through visual and acoustic warnings if it senses an accident is likely to happen. It also primes the Brake Assist function to ensure maximum stopping power as soon as the driver touches the brake pedal. Unlike some systems on the market, which work only at urban speeds and are intended to prevent minor damage, COLLISION PREVENTION ASSIST functions from speeds of 20 mph and aims to help Mercedes-Benz B-Class owners avoid colliding with the car in front in potentially dangerous circumstances.

Mercedes-Benz safety experts believe COLLISION PREVENTION ASSIST can prevent around 20 per cent of all nose-to-tail collisions and reduce the severity of them in another 25 per cent of cases.

ADAPTIVE BRAKE

COLLISION PREVENTION ASSIST works in conjunction with the standard-fit ADAPTIVE BRAKE system, which incorporates the ABS anti-lock brakes. If the driver abruptly releases the accelerator pedal – the first reaction in a potential emergency – ADAPTIVE BRAKE primes the brake pads so that they come into light contact with the brake discs. Should emergency braking then be required the necessary braking pressure is achieved instantly. During wet weather it systematically applies brake contact to dry the brake discs. The contact is so light that the driver is unaware of this happening.

Hill Start Assist is also standard to ensure the new Mercedes-Benz B-Class always pulls away smoothly, even on the steepest uphill gradient. It prevents the vehicle from unintentionally rolling backwards when setting off, and keeps the car stationary whenever it comes to rest without the driver having to keep a foot on the brake pedal.

PRE-SAFE®

This anticipatory Mercedes-Benz PRE-SAFE® occupant protection system is available as an option on the new B-Class (£345). Using the ESP® Electronic Stability Programme sensors, it can recognise potentially dangerous situations and transmit the information to the car’s electronic control units within milliseconds so that the seat belts and airbags deploy with maximum effect in the event of a collision. It also closes any open windows and the sunroof if fitted.

DISTRONIC PLUS

Versions of the new Mercedes-Benz B-Class fitted with the 7G-DCT (dual-clutch transmission) can be specified with the DISTRONIC PLUS adaptive cruise control system (£900), which delivers the twin benefits of enhanced safety in heavy traffic with the minimum of stress on the driver. Two short-range sensors behind the front bumper and a long-range sensor behind the radiator grille help the driver maintain a safe gap to the car in front by braking the B-Class to a standstill if necessary and accelerating it again in response to the flow of traffic. It functions at speeds between zero and 125 mph and is particularly effective in heavy stop-start traffic. If it senses the gap to the car ahead is closing too quickly it issues visual and audible alerts.

Intelligent Light System

The optional Mercedes-Benz Intelligent Light System (£1,460 – SE, £850 – Sport) incorporating bi-Xenon headlights with LED daytime running lights, Adaptive High Beam Assist and cornering light function provides the ideal illumination for the type of road being driven on and the speed of the car.

It features five light functions – country mode, motorway mode, enhanced foglamps, active light function and cornering light function -designed specifically for differing driving situations or weather conditions.

Low beam is replaced by country road mode, which illuminates the driver’s side of the road more brightly than the centre. At speeds above 55 mph, motorway mode takes over, increasing the driver’s range of vision by up to 60 per cent. This happens in two stages: the Intelligent Light System first increases the light intensity and then, at 68 mph, the beam on the driver’s side is elevated slightly. Motorway mode has a range of around 120 metres and is designed to increase the driver’s range of vision by about 50 metres compared with conventional low-beam headlamps.

The enhanced foglamps are activated at speeds below 40 mph as soon as the rear foglamp is switched on. The bi-Xenon headlamp on the driver’s side of the car pivots by eight degrees and is lowered at the same time. This adjustment illuminates the centre section of the road more brightly and reduces glare from light reflected back by the fog.

The active light and cornering light functions are switched on automatically, depending on the steering angle, rate of turn and vehicle speed. The active light function pivots the headlamps sideways by up to 15 degrees almost instantaneously, greatly enhancing the driver’s view of the road.

The cornering light function improves safety at crossroads, T-junctions and on tight bends. It is activated automatically when the driver turns the steering wheel at speeds below 40 mph.

The Intelligent Light System includes Adaptive High-beam Assist, which constantly and automatically adjusts the range of the headlamps based on the distance of oncoming vehicles or those in front of the car. The Mercedes-Benz system uses graduated steps between “dipped” and main beam rather than a sudden switching between two modes, which means the driver enjoys the best possible visibility for more of the time.

Speed Limit Assist

Speed Limit Assist uses a camera mounted in the upper part of the windscreen and compares the information with data stores in the satellite navigation system to recognise approaching speed limit signs. It then displays the speed limit in the instrument panel. It comes as part of the COMAND Online system (£2,100).

Lane Tracking Package

The Mercedes-Benz Lane Tracking Package (£785) is designed to prevent owners from straying into the path of other cars when changing lanes or should they become distracted while at the wheel. It consists of Lane Keeping Assist and Blind Spot Assist. Lane-Keeping Assist reads the lane markings on the road and, if the car crosses them unintentionally, it alerts the driver by gently vibrating the steering wheel. Blind Spot Assist uses two radar sensors to detect a vehicle approaching from behind that the driver may not have seen. If the Mercedes-Benz B-Class driver then attempts to pull out to overtake, it issues visual warnings in the door mirrors and an audible warning within the car. It functions at speeds above 30 mph.

Source