GM Service Manual Online
For 1990-2009 cars only

Object Number: 585721  Size: MF
ABS Components
Antilock Brake System Schematics
Data Link Connector Schematics
Handling Electrostatic Discharge Sensitive Parts Notice
Handling Electrostatic Discharge Sensitive Parts Notice

Circuit Description

The PCM monitors various parameters and will not allow operation of the Enhanced Traction system (ETS) if any PCM parameter falls below a predetermined value.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The PCM detects a malfunction and then causes the ETS to shutdown until the malfunction is corrected.

Action Taken When the DTC Sets

    • A DTC C1275 is stored.
    • The ETS is disabled.
    • The TRAC OFF indicator is turned ON.
    • The ABS remains functional.
    • If the ETS is no longer inhibited, the indicator lamp will be turned OFF but the DTC will still be stored.

Conditions for Clearing the DTC

    • The condition for the DTC is no longer present and the scan tool clear DTC function is used
    • 100 ignition cycles have passed with no DTCs detected

Diagnostic Aids

Check for PCM DTCs. If no PCM DTC is stored, DTC C1275 may have set due to a hot engine or a hot transaxle (both normal conditions). No repairs should be made to the ETS System. ETS will remain disabled until the EBTCM receives a traction allowed message from the PCM. When the EBTCM receives this message, it re-enables the ETS and turns OFF the TRAC OFF indicator. Any further references for diagnosis should be taken from Engine Controls.

Step

Action

Value(s)

Yes

No

1

Did you perform the ABS Diagnostic System Check?

--

Go to Step  2

Go to Diagnostic System Check - ABS

2

  1. Turn the ignition switch to the RUN position, engine off.
  2. Use the Scan Tool in order to read the DTCs.
  3. Make note of the DTCs.

Are any other ABS or PCM DTCs set?

--

Go to Diagnostic Trouble Code (DTC) List/Type or Diagnostic Trouble Code (DTC) List/Type in Engine Controls-3.1L (LG8)

Go to Step  3

3

  1. Clear the DTCs.
  2. Turn the ignition switch to the OFF position.
  3. Turn the ignition switch to the RUN position, engine off.

Does DTC C1275 reset?

--

Go to Step  5

Go to Step  4

4

  1. Start the engine and test drive the vehicle at a speed of at least 16 km/h (10 mph).
  2. Initiate an enhanced traction assisted take off.
  3. Repeat the above drive cycle sequence two more times.

Did the DTC C1275 set in these last three drive cycles?

--

Go to Step  5

System OK

5

Perform a Powertrain OBD System Check. Refer to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls.

Did the vehicle pass the OBD system check?

--

Go to Step  6

Go to Diagnostic Trouble Code (DTC) List/Type

6

Replace the EBCM. Refer to Electronic Brake Control Module Replacement .

Is the repair complete?

--

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  2

System OK