Driving and Driving Safety
171
The events below inform the driver of PSM control
operations and warn him to adapt his driving style
to the road conditions:
– The multifunctional information light on the
instrument panel flashes.
– Light in the PSM Off button flashes.
– Hydraulic noises can be heard.
– The vehicle decelerates and steering-wheel
forces are altered as the PSM controls the
brakes.
– Reduced engine power.
– The brake pedal pulsates and its position is
changed during braking.
In order to achieve full vehicle deceleration,
foot pressure must be increased after the
brake pedal has begun vibrating.
Examples of PSM control operations
– If the “front wheels” of the vehicle drift on a
bend, the engine power is reduced and the
rear wheel on the inside of the bend is braked
if necessary.
– If the rear of the vehicle swings out on a bend,
the front wheel on the outside of the bend is
braked.
– Pre-filling the brake system:
The brake system is prepared for possible
subsequent emergency braking if the acceler-
ator pedal is released suddenly and quickly.
The brake system is pre-filled, and as a result
the brake pads then already slightly touch the
brake discs.
– Brake booster:
In the event of an emergency braking operation
where the pedal force is insufficient, a brake
booster provides the braking pressure neces-
sary for maximum deceleration at all 4 wheels.
Combined operation of PSM and
PTM/PTM Plus
In order to ensure optimum stabilisation of the
vehicle, the centre differential lock (PTM) and
where appropriate also the rear differential lock
(PTM Plus) are also opened when PSM inter-
ventions occur.
Tip on driving
When PSM is switched off, wheel-specific brake
interventions and the traction control system
(TCS) are also inactive.
The automatic brake differential (ABD) remains on.
Off-road PSM
(PSM in Low Range off-road programme)
When the Low Range off-road driving programme
is active, an off-road PSM specially matched to
off-road driving is activated to enhance traction.
In order to improve driveability on difficult terrain,
the response of the off-road PSM is less sensitive
in the low speed range when the vehicle is
operated in the Low Range off-road driving
programme.
If the brakes are highly stressed, the automatic
brake differential (ABD) switches itself off to
protect the brakes. It remains deactivated until the
brake system has cooled sufficiently again.
Engine drag torque control (MSR)
In conditions of excessive slip, the engine drag
torque control system prevents all driven wheels
locking up when the vehicle is overrunning. This is
also the case for downshifts on a slippery road.
Содержание Turbo 2007
Страница 105: ...104 Lights Direction Indicators and Windscreen Wipers ...
Страница 107: ...106 Multi Purpose Display and Instruments ...
Страница 224: ...Parking 223 Parking ParkAssist 224 Swivelling down mirror glass as parking aid 228 Garage door opener 228 ...
Страница 347: ...346 Index ...