Asr System (Electronic Anti-Skid 22 Device); Activation; Fault Indicators; Msr Function (Engine Braking Torque Adjustment) - Maserati Quattroporte Automatic Owner's Manual

M139_UM_ing.book Page 44 Friday, September 5, 2008 8:19 AM
ASR system (electronic
anti-skid device)
The ASR system prevents skidding of
the driving wheels during acceleration
by means of the engine control unit
(spark advance delay, engine throttle
2
opening reduction and fuel injection
cut-out) and of the rear brakes.
The ASR system enhances the vehicle
stability and improves active safety
while driving, especially under the
following conditions:
– internal wheel skidding on curves
because of the dynamic load
variations or excessive acceleration
– excessive power transmitted to the
wheels, also in relation to the
roadbed conditions
– acceleration on slippery, snowy or icy
roadbeds
– loss of road grip on wet roadbeds
(aquaplaning).
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ASR system (electronic anti-skid device)
The ASR system works together with
the electronic suspension control
system: under normal conditions
(SPORT mode off), stability in low and
medium grip conditions has priority,
while with SPORT mode active, the
system favours traction, thereby
optimising vehicle's performance on
dry asphalt.

Activation

The ASR system is automatically
activated every time the engine is
started and can be cut-out by pressing
button A for about 2 seconds.
Press button A again to reactivate the
system.
The dark yellow warning light on
the instrument panel flashes during all
the activation phases.

Fault indicators

In the event of a fault, the system is
automatically disabled and cannot be
reactivated. While driving, this
condition is signalled by the amber
warning light on the instrument
panel that illuminates together with
the message "ASR unavailable go to
dealer".
MSR function (engine braking
torque adjustment)
The ASR system also controls the
engine braking torque when the
accelerator pedal is released under low
grip conditions (snow, ice etc.): in
these conditions, in fact, the engine's
high braking torque may cause
instability of the vehicle.
The system, using the same sensors as
the ABS, detects the skidding arising
on one or both of the driving wheels
when the accelerator is released and
opens the motor driven throttle for the
engine supply system, thereby
reducing the braking torque and
restoring the driving wheels'
maximum grip conditions.
WARNING: The maximum deceleration
that can be obtained with the engine
braking always depends on the tyre
grip on the roadbed. Snow or ice
obviously reduce grip levels.