Volkswagen Multivan 2010 Service Training page 31

The system has the following new functions in addition
to those already named:
Function
ARP
(active rollover protection)
Maximum brake support
Ready alert brake (prefill)
Fading brake support
Hydraulic brake assistant
Rain brake support
Trailer stabilisation
Tyre pressure monitor TPM
Functional description
ARP minimises the risk of rolling over when cornering. If the transverse acceleration
threshold value set for the individual vehicle is exceeded during cornering, the engine
torque is reduced and the front wheel on the outside of the curve is braked. This reduces
the rollover torque. Due to the large payload of the T5 2010, the vehicle load is generally
included in the ARP control calculations.
The control unit uses the longitudinal acceleration sender to register the current
acceleration and uses the ratio between this and the engine torque, including the overall
ratio, to calculate 3 different load conditions (unladen, half-laden and fully laden). Then,
according to the load condition, the ESP control unit controls the optimum application
point for ESP.
Increased braking power (especially when vehicles are laden) during ABS control. When
the front axle starts ABS-controlled braking, the brake pressure at the rear axle is
increased until this also enters ABS-controlled braking.
If the foot is withdrawn rapidly from the accelerator pedal then it can be expected that
emergency braking will follow.
Therefore, in such situations, the brake pads are moved up into contact with the brake
disc so that brake intervention can be more rapid, thereby reducing the braking distance.
If fading is detected (reduction in brake effectiveness when brakes are hot) then
the brake pressure is increased using the ABS pump, thereby improving the braking
effect.
The pneumatic brake assistant is replaced by a hydraulic brake assistant in the T5 2010.
The brake assistant is activated when the driver presses the brake pedal quickly, but not
powerfully enough. The system interprets this as panic braking, so the brake pressure is
increased by the ABS pump until ABS control starts.
As soon as the windscreen wipers are switched on, the brake pads are brought into
contact briefly with the brake disc at regularly intervals, thereby removing any film of
water from the brake discs that may be present due to rain/splash water. This improves
the responsiveness of the brake system in wet weather.
When driving with a trailer, trailer stability assist keeps the vehicle and the
trailer on track. According to the requirements, individual wheels of the towing vehicle
are braked or deceleration is initiated by reducing the engine torque. This means the
vehicle/trailer combination is stabilised in case there is a risk of it becoming unstable.
At present, this function is only possible if the trailer tow hitch is ordered as initial
equipment.
The ESP control unit incorporates an indirectly measuring tyre pressure monitor for
detecting a loss in tyre inflation pressure by evaluating the rolling circumferences of the
wheels. If a tyre loses pressure, this is detected within a few minutes of driving by means
of specific evaluation of the wheel speeds.
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