GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC C0179: System Thermal High

Circuit/System Description

The electronic brake control module (EBCM) monitors the duration and how many times antilock brakes or the traction control is activated to calculate an estimated temperature of the brake components to prevent overheating.

Conditions for Running the DTC

Ignition ON.

Conditions for Setting the DTC

The EBCM detects the temperature of the brakes is too high.

Action Taken When the DTC Sets

    • The EBCM disables the Antilock Brake System (ABS)/TCS/Vehicle Stability Enhancement System (VSES) for the duration of the ignition cycle.
    • A DIC message and/or a warning indicator may be displayed.

Conditions for Clearing the DTC

    • The EBCM calculates the brakes have cooled sufficiently.
    • The EBCM clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Diagnostic Aids

DTC C0179 does not indicate a malfunction has occurred. This DTC indicates their was excessive ABS or Traction Control activation that could cause high temperatures.

Reference Information

Schematic Reference

Antilock Brake System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

ABS Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module Referencesfor scan tool information.

Circuit/System Verification

Verify that the DTC sets outside of the Conditions for Running and Setting. Since most occurrences of this DTC are caused by an excessive braking or Traction Control usage, review with the customer the conditions under which the DTC set.

If the DTC set within the Conditions for Running and Setting, the brake system is operating as designed.