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 Descriptors

DTC C0131 5A
- Pressure Circuit Plausibility Failure

Circuit/System Description

The electronic brake control module uses input from the brake pressure sensor for vehicle stability enhancement system functions. The brake pressure sensor is internal to the brake pressure modulator valve.

Conditions for Running the DTC

* Ignition ON.

* Ignition voltage is greater than 10 volts.

Conditions for Setting the DTC

* Internal pressure sensor fault.

* The electronic brake control module detects the brake pressure is increasing when braking, and did not receive a message that the brake pedal is applied.

* The electronic brake control module detects the brake pressure does not increase when braking, when it received a message that the brake pedal is applied.

Action Taken When the DTC Sets

* A driver information system message and/or a warning indicator may be displayed.

* The electronic brake control module disables the ABS, the traction control system and the vehicle stability enhancement system for the duration of the ignition cycle.

Conditions for Clearing the DTC

* The condition for the DTC is no longer present.

* The electronic brake control module clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles.

Note: During normal diagnostic and/or repair verification technicians may find that the ABS, Traction control and/or Stability indicators may be ON with NO DTCs displayed by the electronic brake control module. Do not replace the electronic brake control module for this condition.

If the ABS, Traction control and/or Stability indicators are ON with no DTCs set, perform the following steps:

1. Remove the key from the ignition, open and close the driver's door to turn off retained accessory power, and wait 60 seconds.

2. Ignition ON, if the ABS, Traction control and/or Stability indicators are still illuminated, operate the vehicle at speeds greater than 15 km/h (10 mph) to complete the self test. The electronic brake control module should request all indicators to turn OFF.

3. If the indicators remain ON with no DTCs set after the drive cycle, disconnect the battery for at least 60 seconds then reconnect the battery.

4. Operate the vehicle at speeds greater than 40 km/h (25 mph), the electronic brake control module should request the indicators to turn OFF.

Diagnostic Aids

DTC C0131 can set if the electronic brake control module is loosely attached to the hydraulic unit. The mountings should be checked for the proper torque.

Reference Information

Schematic Reference

Antilock Brake System Schematics [1][2]Antilock Brakes / Traction Control Systems

Connector End View Reference

Component Connector End Views A/C Compressor Clutch

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 Control Module References for scan tool information

Circuit/System Testing

1. Apply and release brake pedal. Verify brake lamps operate properly.

• If brake lamps do not operate properly, refer to Symptoms - Lighting Symptoms - Lighting.

2. Perform the scan tool electronic brake control module Brake Pressure Sensor Calibration. Refer to Brake Pressure Modulator Valve Pressure Sensor Calibration Testing and Inspection.

3. Replace the brake pressure modulator valve.

Repair Instructions

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

* Brake Pressure Modulator Valve Replacement Brake Pressure Modulator Valve Replacement

* Control Module References Control Module References for electronic brake control module replacement, programming and setup