C0131

DTC C0131

Diagnostic Instructions

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

DTC Descriptor
DTC C0131 00
- Antilock Braking System Pressure Circuit Malfunction

DTC C0131 4B
- Antilock Braking System Pressure Circuit Calibration Not Learned

Diagnostic Fault Information





Circuit/System Description

The brake pressure sensor is integral to the brake pressure modulator valve assembly. The electronic brake control module (EBCM) monitors the brake pressure sensor supply voltage and the signal voltage. The body control module (BCM) sends a serial data message when the brake pedal is applied.

Conditions for Running the DTC

Ignition ON.

Conditions for Setting the DTC

* The brake pressure sensor supply voltage is less than 4.4 V or greater than 5.4 V.
* The brake pressure sensor signal offset is out of the specified range.
* The brake pressure sensor signal is out of the specified range.

Action Taken When the DTC Sets

* The EBCM disables the ABS, traction control and stability control for the duration of the ignition cycle.
* The ABS indicator turns ON.
* The traction control/stability control-active indicator turns ON.

Conditions for Clearing the DTC

* A current DTC clears when the diagnostic runs and passes.
* The EBCM will turn OFF the indicators and enable the system functions in the next ignition cycle.

Reference Information
Schematic Reference

Antilock Brake System Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

ABS Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing For Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

Ignition ON, observe the scan tool Brake Pressure Sensor parameter. The reading should be 0 V, when the brake pedal is released and greater than 1 V, when the brake pedal is applied.

Circuit/System Testing

1. Verify that DTC C0131 4B is not present.

• If DTC C0131 4B is present, perform the Brake Pressure Modulator Valve Pressure Sensor Calibration (Testing and Inspection).

2. Observe the stop lamps while applying and releasing the brake pedal. Verify the stop lamps operate properly.

• If the stop lamps do not operate properly, refer to Symptoms - Lighting (Symptoms - Lighting).

3. Replace the brake pressure modulator valve assembly and verify the DTC does not reset.

• If the DTC resets replace the K17 Electronic Brake Control Module (EBCM).

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Brake Pressure Modulator Valve Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for EBCM replacement, programming and setup