brake sensor Mercury Grand Marquis 1999 Owner's Manuals

TRACTION CONTROLY(IF EQUIPPED)
Your vehicle may be equipped with the optional Traction Controly
system. This system helps you maintain the stability and steerability of
your vehicle. It is especially useful on slippery and/or hilly road surfaces.
The system operates by detecting and controlling wheel spin. The system
borrows many of the electronic and mechanical elements already present
in the anti-lock braking system (ABS).
Wheel-speed sensors allow excess rear wheel spin to be detected by the
Traction Controlyportion of the ABS computer. Any excessive wheel
spin is controlled by automatically applying and releasing the rear brakes
in conjunction with engine torque reductions. Engine torque reduction is
realized via the fully electronic spark and fuel injection systems. This
process is very sensitive to driving conditions and very fast acting. The
rear wheels ªsearchº for optimum traction several times a second and
adjustments are made accordingly.
The Traction Controlysystem will allow your vehicle to make better use
of available traction on slippery surfaces. The system is a driver aid
which makes your vehicle easier to handle primarily on snow and ice
covered roads.
During Traction Controlyoperation you may hear an electric motor type
of sound coming from the engine compartment and the engine will not
ªrev-upº when you push further on the accelerator. This is normal
system behavior.
If you should become stuck in snow or ice or on a very slippery road
surface, try switching the Traction Controlysystem off. This may allow
excess wheel spin to ªdigº the vehicle out and enable a successful
ªrockingº maneuver.
If the Traction Controlysystem is cycled excessively, the brake portion
of the system will shut down to prevent the rear brakes from
overheating. A limited Traction Controlyfunction using only engine
torque reduction will still control wheels from over-spinning. When the
rear brakes have cooled down, the system will again function normally.
Anti-lock braking is not affected by this condition and will function
normally during the cool down period.
If the engine coolant temperature is below þ23ÉC (þ10ÉF) the engine
torque reduction portion of the Traction Controlysystem isNOTactive.
The system will operate normally when the engine coolant warms up.
Driving
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