Z Series E85 Z4 3.0i (N52) ROADST
axle slip in dependence of the front axle.
CBC: Cornering Brake Control
CBC is an extension of ABS. CBC enhances driving stability if the brakes are applied when cornering.
Advantage: If the brakes are applied in a corner, optimum brake force distribution ensures optimum tracking
stability.
When cornering, even very light braking can shift the axle-load distribution to the left or right so that driving
stability is impaired. If required, CBC generates a stabilising load moment when the brakes are applied lightly
outside the ABS intervention range.
ASC: Automatic stability control
ASC prevents the wheels from spinning when the vehicle is accelerating.
Advantage: Improved traction. The vehicle remains stable.
If one of the wheels of the drive axle is on a high-grip surface and the other is on a slippery surface, the wheel
tending to skid is braked.
ASC also intervenes in the engine control (to reduce the ignition angle, injection quantity, throttle valve setting).
DTC: Dynamic traction control
DTC is a version of DSC that has been optimised for forward momentum in certain road conditions. Dynamic
traction control (DTC) offers better traction as a trade-off against a reduction in stability in some circumstances.
Consequently, its use should be reserved for exceptional conditions. It is advisable to briefly activate DTC in the
following exceptional circumstances:
•
To rock the vehicle free or pull away in deep snow or on a loose surface.
•
When driving on snowy uphill stretches, in slush and on roads that have not been cleared.
•
When driving with snow chains.
The DTC function approximates to that of DSC with a slightly modified control strategy.
DTC can be activated by deactivating DSC (DTC button). DTC intervenes in the braking actions to imitate the
function of a conventional differential lock. This effect of this is to increase the input torque on those wheels that
are on a higher-friction surface.
Advantage: Higher traction is available with DTC.
Vehicle stabilisation intervention (e.g. reduced power output) is made slightly later than with DSC. In certain
situation, the driver has to intervene more intensively himself to stabilise the vehicle.
MSR: Engine drag torque control
The drive wheels are able to lock if a lower gear is selected of load is abruptly changed on a slippery road
surface.
Engine drag torque control provides protection against locking drive wheels.
Advantage: The drive wheels retain their lateral stability in overrun mode.
The wheel speed sensors tell MSR as soon as the wheels are about to lock. MSR then briefly reduces the
engine's drag torque by opening the throttle slightly.
DBC: Dynamic brake control
DBC supports the driver in emergency braking situations. It does this by automatically increasing braking
pressure when the brake pedal is not depressed with sufficient force.
Advantage: Shortest possible braking distances in emergency braking situations by achieving ABS regulation on
all four wheels.
SBT Dynamic Stability Control Mk60E5 E85, E86, E87, E90, E91, E92, E93
BMW AG - TIS
16.02.2013 10:58
Issue status (12/2007) Valid only until next DVD is issued
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