GM Service Manual Online
For 1990-2009 cars only

Circuit Description

After the traction control switch (TCS) is pressed and released, the LED on the switch illuminates. The body control module (BCM) illuminates the LED by supplying adequate current to the high side of the LED.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B0827 Traction Control System Off Indicator Circuit Low

Conditions for Running the DTC

    • The ignition is ON.
    • The body control module (BCM) is commanding the traction control switch LED ON.

Conditions for Setting the DTC

The BCM detects low voltage on the TCS requested indicator control circuit when the LED is switched ON.

Action Taken When the DTC Sets

The BCM sets DTC B0827 as a current DTC for as long as the condition is present.

Conditions for Clearing the DTC

The DTC clears automatically from Current status when the fault is corrected or when the Conditions for Running the DTC are not being met. Use a scan tool to clear the DTC from History status.

Diagnostic Aids

An intermittent short to ground on the TCS requested indicator control circuit is the most likely cause of a history DTC when no problem is found. When the Conditions for Setting this DTC are present, the traction control switch LED cannot illuminate.

Test Description

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

  1. This step tests for a short in the traction control switch. Normally, DTC B0828 sets when the TCS requested indicator control circuit is opened.

Step

Action

Yes

No

Schematic Reference: Antilock Brake System Schematics and Body Control System Schematics

Connector End View Reference: Antilock Brake System Connector End Views and Data Communication Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Turn OFF the ignition for 5 seconds.
  2. Turn ON the ignition.
  3. Press and release the traction control switch once.

Does the DTC set?

Go to Step 3

Go to Diagnostic Aids

3

  1. Turn OFF the ignition.
  2. Remove the instrument panel center trim bezel to access the traction control switch harness connector.
  3. Disconnect the traction control switch harness connector.
  4. Turn ON the ignition.

Does DTC B0828 set?

Go to Step 6

Go to Step 4

4

Test the traction control switch (TCS) requested indicator control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 7

Go to Step 5

5

Replace the body control module (BCM). Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 7

--

6

Replace the traction control switch. Refer to Accessory Switch Replacement .

Did you complete the replacement?

Go to Step 7

--

7

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 3

System OK