Chart D Traction Control Operation Check W/No DTC's Set

Chart D Traction Control Operation Check W/No Diagnostic Trouble Codes Set:

Chart Test Description:
Test numbers refer to circled numbers on the diagnostic chart.
1. Traction control system should interpret the elevated front wheels as an icy or free spin condition. At 1/2 throttle a properly operating system will allow both front wheels to spin up quickly to about 20-25 mph and then slow down (but not stop) to about 5-10 mph and have a jerky appearance. The "TRACTION ACTIVE" message should display on the DIC. The pump motor should also be heard.
2. System is building up pressure to the front brake and operating correctly.
3. System is not building up pressure to the front brakes. Possible air or dirt in the system or a low fluid level.

Diagnostic Aids:
The Brake Switch must be properly adjusted to prevent an erroneous brake application input to the EBTCM. Incorrect adjustment may prevent brake intervention during traction control operation. Also, the EBTCM receives TCC switch status over serial data from the PCM. If serial data is lost or the switch remains engaged, brake intervention during traction control may be lost. Monitor PCM TCC switch input P171 while cycling brake switch. The input should cycle "HI" when the pedal is pressed and "LO" when it is released.