GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The Traction Control indicator is controlled by the instrument cluster (IPC) via serial data messages from the EBCM. The EBCM send a serial data message to the IPC to illuminate the Traction Control indicator when the EBCM has disabled TCS due to a DTC. The Traction Control indicator will also turn ON during the instrument cluster bulb check. When the ignition switch is turned to ON, the Traction Control indicator will turn ON for approximately 3 seconds and then turn OFF.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. Use the scan tool to check the normal state of the Traction Control indicator control.

  2. Ensures that the instrument cluster can operate the Traction Control indicator.

Step

Action

Yes

No

Schematic Reference: Antilock Brake System Schematics

Connector End View Reference: Antilock Brake System Connector End Views or Displays and Gages Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the TCS Warning Indicator/Message parameter in the DRP/ABS/TCS data list.

Does the scan tool display Off?

Go to Step 3

Go to Step 4

3

  1. Turn OFF the ignition.
  2. Turn ON the ignition, with the engine OFF.
  3. Observe the Traction Control indicator on the instrument cluster (IPC) during the bulb check.

Does the Traction Control indicator illuminate during the bulb check and then turn OFF?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 5

4

Inspect for poor connections at the harness connector of the electronic brake control module (EBCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs.

Did you find and correct the condition?

Go to Step 8

Go to Step 6

5

Inspect for poor connections at the harness connector of the instrument panel cluster (IPC). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs.

Did you find and correct the condition?

Go to Step 8

Go to Step 7

6

Replace the EBCM. Refer to Control Module References for replacement, setup and programming.

Did you complete the replacement?

Go to Step 8

--

7

Replace the IPC. Refer to Control Module References for replacement, setup and programming.

Did you complete the replacement?

Go to Step 8

--

8

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2