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 traction control operation if any parameter falls below a specified value.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The PCM detects a malfunction and then causes TCS shut down until the malfunction has been corrected.

Action Taken When the DTC Sets

    • A DTC C1278 is stored (This is a temporary malfunction)
    • The TCS is disabled
    • The TRACTION OFF indicator is turned on
    • ABS remains functional.

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

This code is for information only. As an aid to the technician, this code indicates that there are no problems in the ABS/ETS/TCS system. Any further references for diagnostic information should be taken from Engine Controls.

Step

Action

Value(s)

Yes

No

1

Did you perform the ABS Diagnostic System Check?

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Go to Powertrain On Board Diagnostic (OBD) System Check

Go to Diagnostic System Check - ABS