Mercedes-Benz B-Class

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The Mercedes-Benz B-Class (W245) is a compact MPV from Mercedes-Benz introduced in March 2005. It is essentially an enlarged A-Class keeping the same engine and suspension system. Like the A-Class, the B-Class is a front wheel drive vehicle, a significant departure for the company.

Mercedes Benz named this vehicle Compact Sports Tourer (CST) instead of "hatchback", like its R-Class model, which is called the Grand Sports Tourer (GST) instead of "minivan".

It was released in Europe in the late spring of 2005 and in Canada since the fall of 2005. Plans to import the car to the US were put on hold due to a strong euro, that would price the vehicle uncompetitively in the US market.

1 Design
2 Specifications
3 Sandwich floor concept
4 Driving assistants
5 Inside comfort
- 5.1 Air conditioning
- 5.2 Sunroof
6 Safety
7 Making room
8 Engines
- 8.1 Speeds
9 Wheel axles
10 Profitability and impact on the Mercedes Benz brand
11 External links

[edit] Design

Keeping in mind its United States' market in comparison with the A-Class and indeed emulating the R-Class, the aspect of the B-Class was stylized from the back to the nose. Some of the tiny stylistic details that gave certain personality to the Baby-Benz (popular name of the A-Class) were removed by Mercedes Benz. In particular, the front of the vehicle was lengthened deliberately (although maintaining its own proprietary Sandwich anti-crash system). The panoramic all-around windows were made more sober without any wedge-form detail.

It has a wide space to sit (as much as in a true E-Class) though flexible enough to circulate in crowded streets (like in Europe).

[edit] Specifications

Specification	B180 CDI	B200 CDI	B150	B170	B200	B200 Turbo
length (m)	4.270	4.270	4.270	4.270	4.270	4.270
width (m)	1.777	1.777	1.777	1.777	1.777	1.777
height (m)	1.603	1.603	1.603	1.603	1.603	1.603
wheelbase (m)	2.778	2.778	2.778	2.778	2.778	2.778
Kerb weight (kg)	1435	1435	1300	1310	1345	1370
tank capacity(l)	54	54	54	54	54	54
tank reserve(l)	6	6	6	6	6	6
Cylinders	4/in-line	4/in-line	4/in-line	4/in-line	4/in-line	4/in-line
Output hp/rpm	109/4200	140/4200	95/5200	116/5500	136/5750	193/5000
Torque Nm/rpm	250/1600-2600	300/1600-3000	140/3500-4000	155/3500-4000	185/3500-4000	280/1800-4850
Top Speed (mph)	114	124	108	114	122	140
Tires	205/55 R 16	205/55 R 16	195/65 R 15	195/65 R 15	205/55 R 16	215/40 R 18

[edit] Sandwich floor concept

The B-Class W245 maintains the sandwich floor concept.

The powertrain (engine and transmission) moves beneath the passenger cell (located at high seating position) in the event of a big frontal impact. According to a study[1]: "the front section of the A-Class would have to be considerably longer in order to offer the same impressive level of occupant safety in the event of a heavy frontal impact".

These are two historical automobile innovations, patented by Mercedes Benz as:

DE 43 26 396 C 2: motor car with drive unit tilted at an acute angle against the horizontal
DE 44 00 132 C1: Firewall construction for a motor car with front-mounted drive unit

As a secondary benefit, thanks to the fact that the seats have been raised by 20 cm, the passengers are taken away from the more common area of lateral impact in traffic accidents.

[edit] Driving assistants

The B-Class presents a wide interior, basically due to the Sandwich floor.

Also, Mercedes-Benz developed the concept of TAF (Touch And Feel), which applies to all the devices of the automobile, tactile and ergonomic improvements.

The multifunction steering wheel (standard feature) allows the driver to use his/her thumbs to control the radio, telephone and other systems. There are Power Assisted Steering (standard feature) aids in the control of the automobile, varying according to the speed.

The COMAND APS is a system where Route instructions are given to the Navigation system, and the information is provided via SMS. The car radio, DVD and telephone controls are combined into a single unit with a 6.5 inch screen. The options are: standard Audio 20 radio/single CD, Audio 50 APS or COMAND APS.

Parktronic emits warning tones and uses multiple LEDs to indicate how far the car is from an obstacle.

W169 defines the Light & Sight package with several benefits:

Bi-xenon HID headlamps (optional feature) with gas-discharge bulbs for the dipped beam
Cornering lights (standard feature) where the main-beam dips at road junctions and tight corners
Active light system (standard feature) where the beams follows the steering movements
Headlamp Assist (standard feature) is a sensor on the windscreen monitoring ambient light levels to automatically switch on the headlamps as required
Rain sensor (standard feature) smoothly adjusts the wiper speed, depending on the intensity of the rainfall.

As a standard addition, when entering a tunnel or an underground garage, the Tunnel Mode closes all windows and the panoramic sliding sunroof.

[edit] Inside comfort

The multicontour seat (optional feature) is composed of a set of small air cushions individually adjusted to the driver's body, as he/she wishes.

[edit] Air conditioning

The W245 units have a powerful air conditioning system, with separate temperature adjustment for driver and front passenger side.

Standard CDI models include a Heater Booster System (standard on CDI models) that instantly floods the interior of the B-Class with hot air. The most advanced system is the Thermotronic (optional feature) that maintains and regulates the temperature in accordance with a sophisticated set of sensors which measure temperature, sunlight, humidity and even pollutant levels in the ambient air, causing all openings to close automatically.

[edit] Sunroof

The new optional sunroof is divided in small panels that can be displaced individually (optional feature). Each one can be controlled separately to selectively administer the shades inside the W245.

[edit] Safety

High-strength and ultra-high-strength steel alloys are combined with high-strength bonded joints.

[edit] Airbags

The B-Class has a generous quantity of airbags. The front airbag is adaptive with two-stage gas generators (standard feature), where the system evaluates the severity of the accident. The B-Class also includes side airbags for head and thorax (standard for driver and front passenger).

Two other additions are optional: Rear Sidebags (optional feature) for side-on collisions in the back seats and Windowbags: large airbags expanding like a curtain from A- to C-pillars in side-on collisions.

[edit] Belts

The belt system of the B-Class W245 is simply surprising. The Adaptive Function (standard feature for driver and front passenger) adapts the force exerted by the belt, relaxing dynamically during the collision. On the contrary, the Tensioners (standard feature) continuously adjust to remove any possible slack, and increase the tightness if necessary. The driver has a report if all the belts are buckled (standard feature).

[edit] Head and neck

Lastly, the active head restraints (standard feature) respond actively to a collision, assuring even more protection.

[edit] Other standard features

While driving there is the Acceleration-Skid Control (ASR) (standard feature) and Electronic Stability Program ESP (standard feature) that reduce the risk of skidding. There are disc brakes on all four wheels, and emergency stops are improved with the Anti-lock braking system (ABS) and Brake Assist (BAS), standard on the Mercedes Benz A-Class. BAS detects emergency braking (most drivers apply the brakes quickly but without enough pressure) and exerts maximum brake pressure.

[edit] Making room

Mercedes Benz imposed a mandate on itself: "Rearrangement first". They avoided having to remove the seats. Instead, to accommodate different possible needs, it is possible to fold the seats forward and then level them at two different heights (standard feature). They provide different final modular space combinations.

Its implementation is provided by two systems:

EASY-VARIO: Both rear-seat cushion sections are folded forward, while the luggage compartment floor can be set to one of two different heights. (Optional feature)
EASY-VARIO-PLUS: Both rear-seat cushion and the front passenger seat are folded forward. This increases the load capacity to as much as 1995 litres. (Optional feature)

[edit] Engines

The Mercedes Benz B-Class W245 has six engines: four of them are petrol (B150, B170, B200, B200Turbo), and two are diesel (B180 CDI, B200 CDI). All the six powerplants are four-cylinder.

The B200 Turbo reaches a yield of 193 hp and 280 Nm of torque, making it one of the most powerful in its displacement class. It sprints from standstill to 100 km/h (60 mph) in a mere 9-11 seconds, and has a top speed of 200 km/h (125 mph).

The B200 CDI reaches 140 hp and 300 Nm of torque. The newly developed direct-injection CDI diesel units possess a common-rail direct injection (standard on CDI models), with additional gains in terms of fuel consumption, exhaust emissions and noise levels.

All the engines meet the tight Euro IV emissions regulation, and a particulate filter system is available as an option for the diesel units (this reduces about 99% of the particulate emissions, without the need for additives).

[edit] Speeds

The speeds are in the range of 5 or 6, manual. Built in compact aluminium. The six-speed version is the standard on B180 CDI, B200 CDI and B200 Turbo.

Mercedes Benz offers as an option the Autotronic Continuously Variable Transmission (CVT) (optional feature) in which the ratios are changed continuously by means of a pulley-wheel variator and a steel thrust belt. This allows the car to accelerate with no interruption of tractive power and attains the maximum output more quickly. This is adjustable according to the client's drive style: economical or sporty.

[edit] Wheel axles

The B-Class is a front-wheel drive car.

In the W245 the dynamic handling was powered in precision tracking and anti-roll support, with the Parabolic Rear Axle (standard feature) that grants a pivotal role in the driving.

Mercedes Benz implemented the modern Selective Damping System (standard feature), where the shock absorber forces are administered differentially, in example under normal conditions (soft absorption) and while cornering at speed (full damping force).

The W245 presents light alloy wheels. With the run-flat feature (continuous mobility or zero-pressure tyres can be driven at normal speeds). There is Tirefit tyre sealant and a tire-pressure-loss warning device by ESP technology (standard feature).

[edit] Profitability and impact on the Mercedes Benz brand

Mercedes-Benz has made a number of confusing announcements - first that a "weak euro" could have produce costs problems[2] and later that the "fall of the dollar" will cause the enterprise to not be profitable [3].

According to some analyses, Mercedes-Benz considers the creation of the A-Class to have already reduced its prestige in Europe, and the company has concentrated its efforts on its other, larger vehicle (and more profitable) lines, in the US.