The chassis: Comfort at the touch of a button

Sep 8, 2015
Should the A-Class deliver a comfortable, sporty or especially efficient ride? DYNAMIC SELECT allows the vehicle characteristics to be modified in a matter of seconds at the touch of a button. DYNAMIC SELECT offers a particularly broad range of settings in combination with the new suspension with adaptive damping.
DYNAMIC SELECT modifies the characteristics of the engine, transmission, suspension, steering and air conditioning according to the driver's wishes. The control units of the individual vehicle components receive a signal and change the particular parameters. At the same time, the selected programme is shown as the current status in the instrument cluster and as a pop-up message in the media display.
Four driving programmes can be selected with the switch in the upper control panel:
  • Each time the ignition is restarted, the balanced, comfort-oriented "Comfort" mode is active as the default setting.
  • More agility and dynamic performance come courtesy of the "Sport" driving programme, which is characterised by a more spontaneous throttle response, sportier steering feedback and firmer damper settings (in conjunction with the new suspension with adaptive damping system, see below).
  • The "Eco" driving programme is designed to keep fuel consumption to a minimum. In addition to the accelerator pedal curve, the output of the seat heating, rear defrost and climate control system are also modified. The so-called "Sailing" function also supports this. If the driver removes his or her foot from the accelerator, the vehicle uses its own kinetic energy and glides along the road in a fuel-saving way.
  • The "Individual" driving programme enables various parameters – from the steering and the powertrain to the suspension – to be adjusted to suit personal preferences. This makes it possible, for example, to combine light and comfortable steering characteristics with a sporty firm suspension set-up. The configuration is selected with the help of the central controller on the media display.
The A 200 d 4MATIC, A 220 4MATIC, A 220 d, A 220 d 4MATIC, A 250 4MATIC, A 250 Sport and A 250 Sport 4MATIC models are equipped with DYNAMIC SELECT as standard. The system is also included as standard in all models with DCT, AMG Line or one of the lowered suspensions. DYNAMIC SELECT is available on request for all other engine variants except the two BlueEFFICIENCY Edition models.
DYNAMIC SELECT offers the full range of setting options in combination with the new suspension with adaptive damping (optional extra). In this case the driver is able to modify the vehicle's damping characteristics using the DYNAMIC SELECT Switch. There is a choice between Comfort mode with comfortable damping characteristics and Sport mode for a sporty and more taut damper set-up. Even in 'Comfort' mode the damping forces are automatically adjusted instantly to the handling dynamics of the vehicle, for example in case of evasive manoeuvres. In Sport mode the effect of the shock absorbers is increased. This enables a significantly more agile driving style. Acceleration sensors measure the vehicle's body movements, and other current information about the vehicle status such as the steering angle, speed of steering angle change and yaw rate is included when calculating the damping characteristics. A proportional valve is actuated electronically at each shock absorber to control the oil flow and therefore the damping characteristics. The damping system is infinitely variable, and the configuration is individual for each wheel.
The suspension experts at Mercedes-Benz were already experimenting with the variance of the damping characteristics before an operational prototype was available: To this end, the engineers fed the so-called ride simulator at the development centre in Sindelfingen with the surface data from real-life test routes and the corresponding suspension data of the adaptive damping system of the A‑Class. In this way, it was possible to conduct virtual test drives with the new suspension on the two seats of the ride simulator at an early stage of the development process – followed by the usual extensive test programme.
The new suspension with adaptive damping is available for all engines except for the two BlueEFFICIENCY Edition models. The two Sport models can be optionally equipped with the AMG-tuned AMG RIDE CONTROL sports suspension with adaptive damping.
In addition, these three suspension set-ups are available for the A-Class:
  • Comfort suspension (standard)
  • Comfort suspension with ride-height lowering (optional, includes sports direct steering and DYNAMIC SELECT). As part of this the body is lowered by 15 mm at the front axle and by 10 mm at the rear axle.
  • Sports suspension with ride-height lowering (standard with AMG Line, includes sports direct steering and DYNAMIC SELECT). Through the firmer set-up of the springs and damping, the sports suspension facilitates a sportier driving style without any great loss of comfort. The ride is likewise lowered by 15 mm at the front axle and by 10 mm at the rear axle.
Mercedes-Benz A-Class, suspension with adaptive damping system