C0131
DTC C0131
Diagnostic Instructions
^ Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Diagnostic System Check - Vehicle
^ Review Strategy Based Diagnosis for an overview of the diagnostic approach. Strategy Based Diagnosis
^ Diagnostic Procedure Instructions provides an overview of each diagnostic category. Diagnostic Procedure Instructions
DTC Descriptor
DTC C0131 00: Antilock Brake System (ABS) Traction Control System (TCS) Pressure Circuit
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 EBCM uses inputs from the body control module (BCM), the brake pedal position sensor and the brake pressure sensor located in the brake pressure modulator valve (BPMV) for more accurate control during a vehicle stability enhancement system (VSES) event.
Conditions for Running the DTC
^ System Voltage is above 9.6 volts.
^ The vehicle speed is greater than 40 km/h (24 mph).
Conditions for Setting the DTC
^ Sensor supply voltage is less than 4.5 volts or greater than 5.3 volts for more than 1 second.
^ Sensor signal voltage is less than 0.12 volts or greater than 3.2 volts for more than 1 second.
^ The EBCM sees the brake pedal is applied, and does not see the brake pressure increase when stopping.
^ The EBCM sees the brake pressure increase, and does not see the brake pedal is applied when stopping.
^ Signal is erratic.
Action Taken When the DTC Sets
If equipped, the following actions occur:
^ The EBCM disables the antilock brake system (ABS), traction control system (TCS) and the vehicle stability enhancement system (VSES) for the duration of the ignition cycle.
^ The Traction Control indicator turns ON.
^ The ABS indicator turns ON.
^ The red brake warning indicator may turn ON.
^ The driver information center displays the Service Stability System message.
Conditions for Clearing the DTC
^ The condition for setting the DTC is no longer present.
^ The EBCM automatically clears the history DTC when a current DTC is not detected in 40 ignition cycles.
Diagnostic Aids
Refer to Bulletin 08-05-22-009 Intermittently Brake Lights (Stops Lamps)
Reference Information
Schematic Reference
^ Antilock Brake System Schematics Diagrams
^ Exterior Lights Schematics Exterior Lights Schematics
Connector End View Reference
Component Connector End Views Connector Views
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 Referencesfor scan tool information
Circuit/System Verification
1. Verify DTC U0140, C0161, C0277 or C0278 is not set.
--> If DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle. Diagnostic Trouble Code (DTC) List - Vehicle
2. Verify the brake pedal position sensor or the brake pedal is not binding causing residual brake pressure to be detected, while the brake lights operate properly.
--> If a condition is found, repair or replace the applicable component.
3. Apply and release the brake pedal. Verify the brake lights operate properly.
--> If the brake lights do not operate properly, refer to Symptoms - Lighting Symptoms - Lighting
4. Ignition ON, observe the scan tool EBCM, VSES Data, BPP Signal parameter. The parameter should be Released when the brake pedal is not applied, and change to Applied when the brake pedal is applied.
--> If not within the specified value, perform the scan tool BCM, BPP Sensor Calibration procedure. Refer to Brake Pedal Position Sensor Calibration . If the DTC resets, replace the brake pedal position sensor.
5. Engine running, brake pedal not applied; verify the scan tool EBCM, VSES Data, Brake Pressure Sensor Input voltage is between 0.45-0.55+V.
--> If not within the specified range, replace the brake pressure modulator valve assembly and verify the DTC does not reset. If the DTC resets, replace the EBCM.
6. Engine running, brake pedal applied; verify the scan tool EBCM, VSES Data, Brake Pressure Sensor Input voltage is between 0.45-4.50+V.
--> If not within the specified range, replace the brake pressure modulator valve assembly and verify the DTC does not reset. If the DTC resets, replace the EBCM.
7. Operate the vehicle within the Conditions for Running and Setting the DTC and verify the DTC does not reset.
--> If the DTC is set replace the brake pressure modulator valve assembly and verify the DTC does not reset. If the DTC resets, replace the EBCM.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
^ Brake Pedal Position Sensor Replacement
^ Brake Pressure Modulator Valve Replacement Brake Pressure Modulator Valve Replacement
^ Control Module References for EBCM replacement, programming and setup Control Module References