GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The PCM sends engine/axle/tire IDs to the EBCM via serial data communications immediately after the modules are powered up.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The EBCM receives invalid information from the PCM.

Action Taken When the DTC Sets

If equipped, the following actions occur:

    • The EBCM disables the TCS.
    • The traction off indicator turns ON.

Conditions for Clearing the DTC

The conditions for setting the DTC are no longer present and you use the scan tool Clear DTCs function.

Diagnostic Aids

Diagnose other ABS or TCS related DTCs prior to diagnosing DTC C0279.

If multiple TCS related DTCs are set, or the vehicle being serviced is not equipped with TCS, verify the correct EBCM is installed in the vehicle.

Test Description

The number below refers to the step number on the diagnostic table:

  1. The PCM must have the correct part number for the specified application.

Step

Action

Yes

No

1

Did you perform the ABS Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - ABS

2

  1. Use a scan tool in order to clear the DTCs.
  2. Turn OFF the ignition for 5 seconds.
  3. Turn ON the ignition and wait 10 seconds.

Does the DTC set?

Go to Step 3

Go to Diagnostics Aids

3

Verify the correct PCM is installed in the vehicle.

Does the vehicle have the correct PCM?

Go to Step 4

Go to Step 6

4

Use the scan tool in order to read the Calibration IDs of the PCM.

Are the PCM Calibration IDs correct?

Go to Diagnostics Aids

Go to Step 5

5

Perform the set up procedure for the PCM. Refer to Powertrain Control Module Programming in Engine Controls - 4.2L.

Did you complete the action?

Go to Step 7

--

6

Important: Perform the set up procedure for the PCM.

Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls - 4.2L.

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