C0161

DTC C0161

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 C0161 00

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Antilock Braking System Brake Sensor Circuit

DTC C0161 5A

-
Antilock Braking System Brake Sensor Circuit Not Plausible

DTC C0161 71

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Antilock Brake System Brake Sensor Circuit Invalid Data

Circuit/System Description

The electronic brake control module (EBCM) detects inputs from the brake pressure sensor, vehicle speed, and a serial data message from the body control module (BCM) that the brake pedal is applied. When the vehicle is stopping the EBCM monitors for the brake pedal is pressed, with the brake pressure increasing and the vehicle is slowing down, or when the vehicle is accelerating, the brake pedal is not pressed and brake pressure is not increasing.

Conditions for Running the DTC

* Ignition ON.

* The vehicle speed is greater than 16 km/h (10 mph).

* The ignition voltage is greater than 10 volts.

Conditions for Setting the DTC

* The vehicle speed is reducing, the brake pressure is increasing, when the brake pedal is not detected as applied.

* The vehicle speed is not reducing, the brake pressure is not increasing, when the brake pedal is detected as applied.

Action Taken When the DTC Sets

* The ABS indicator turns ON.

* The EBCM disables the ABS, traction control system, electronic stability program for the duration of the ignition cycle.

Conditions for Clearing the DTC

* The condition for setting the DTC is no longer present.

* The EBCM clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles.

Reference Information

Schematic Reference

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

Connector End View Reference

Component Connector End Views Fuel Pump and Level Sensor Assembly

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 Verification

Note:
A reprogrammed body control module will set this DTC if the brake pedal position sensor is not learned (Perform the BCM Brake Pedal Position Sensor Learn). Diagnose all other stop lamp DTCs or Symptoms prior to performing this diagnostic procedure.

1. Ignition ON.

2. Verify the Body Control Module, Brake Pedal Position Sensor Learned Released Position parameter is Yes.

• If the parameter is not Yes

Refer to Brake Pedal Position Sensor Calibration .

• If the parameter is Yes

3. Verify that DTC C0277 or C0890 is not set.

• If either DTC is set

Refer to DTC C0277 or C0890 C0277.

• If either DTC is not set

4. Verify the brake pedal position sensor or the brake pedal are not binding causing residual brake pressure to be detected.

• If a condition is found

Repair or replace the applicable component.

• If a condition is not found

5. Verify the scan tool electronic brake control module Brake Pedal Position Sensor parameter changes between Active and Inactive when applying and releasing the brake pedal.

• If the parameter does not change

Refer to Symptoms - Lighting Symptoms - Lighting

• If the parameter changes

6. Replace the Q5 brake pressure modulator.

7. Verify the DTC does not set while operating the vehicle under the Conditions for Running the DTC.

• If the DTC sets

Replace the K17 electronic brake control module.

• If the DTC does not set

8. All OK.

Repair Instructions

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

* Brake Pressure Modulator Valve Assembly Replacement Service and Repair

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