Traction Control System
The Anti-lock Brake System (ABS) and the traction control system consists of the following components:- anti-lock brake control module
- Hydraulic Control Unit (HCU)
- rear anti-lock brake sensors
- rear anti-lock brake sensor indicators
- front anti-lock brake sensors
- front anti-lock brake sensor indicators
- vehicle message center
- yellow ABS warning indicator
- yellow TRAC OFF indicator
The traction control system is operational when the ignition switch is in the RUN position.
It can be disabled by the driver by entering the traction control OFF setting in the vehicle message center. The traction control system will reset and return to the traction control ON setting when the ignition switch is cycled.
The traction control system applies and releases the appropriate front brake to reduce wheel spin and to aid traction if one or both front wheels lose traction and begin to spin during acceleration. TRACTION CONTROL ACTIVE is displayed on the message center during system operation.
The system interacts with the powertrain control module to reduce engine torque if one or both front wheels lose traction and begin to spin during acceleration.
If the traction control system is in operation continually on slippery roads, the anti-lock brake control module may disable the system to prevent overheating of the front brakes.
When the cool down time limit expires, traction control is restored. (Anti-lock braking is fully functional during the cool down period.)
The ABS uses the yellow ABS warning indicator to alert the driver of malfunctions in the system.
The yellow ABS warning indicator will come on for numerous reasons. It warns the driver that the ABS and traction control have been turned off due to a symptom that exists in the ABS system. Normal power-assisted braking remains but the wheels can lock during a panic stop while the yellow ABS warning indicator is on.
In addition to the yellow ABS warning indicator, the traction control system uses the message center to alert the driver of faults unique to the traction control system. CHECK TRACTION CONTROL is displayed on the message center to alert the driver that traction control is disabled due to a symptom in the traction control system.
The anti-lock brake control module monitors system operation and can store all defined DTCs in its memory. The anti-lock brake control module CANNOT recognize some failures. Therefore, if a symptom exists and no DTCs are stored by the anti-lock brake control module, other diagnostic steps must be followed.
The anti-lock brake control module cannot store a DTC if there is no power to the anti-lock brake control module. This condition can be found by using the Anti-Lock Quick Check Sheet.
After the failures have been repaired and you have confirmed the vehicle functions properly, use NGS Tester to clear all DTCs from the anti-lock brake control module.
After clearing the DTCs, the ignition switch must be cycled from RUN to OFF to RUN.
The anti-lock brake control module will automatically clear DTCs that have not recurred after 80 ignition cycles, provided the vehicle has reached 24 km/h (15 mph) between each ignition cycle. (Simply turning the ignition switch from OFF to RUN 80 times will not clear the DTCs.)