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 C0136: Base Brake System Pressure Circuit

Circuit/System Description

The electronic brake control module (EBCM) monitors an internal input from the master cylinder pressure sensor to enhance antilock brake system (ABS) braking and vehicle stability if equipped.

Conditions for Running the DTC

Ignition ON.

Conditions for Setting the DTC

    • When vehicle speed is more than 7 km/h (4 mph), the master cylinder pressure does not change for 30 seconds with the brake applied.
    • When vehicle speed is more than 10 km/h (6 mph), the master cylinder pressure signal is erratic.
    • Master cylinder pressure signal is out of range.
    • Master cylinder pressure is high for 5 seconds with the stop lamp switch signal OFF.

Action Taken When the DTC Sets

    • The EBCM disables traction control system (TCS) and 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 condition for the DTC is no longer present.
    • The EBCM clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Diagnostic Aids

The master cylinder pressure sensor is located internally in the Master Cylinder and is not serviceable.

Reference Information

Schematic Reference

    •  Antilock Brake System Schematics
    •  Exterior Lights 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 References for scan tool information

Circuit/System Verification

Important: It is recommend that the defective components be replaced, and not the complete brake master cylinder assembly.

  1. Verify that DTCs C0131, P0719, P0724 are not set.
  2. If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle.
  3. Replace the EBCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for EBCM and BPMV replacement, setup, and programming