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 Descriptor

DTC C0161 5A
- Antilock Braking System Brake Switch Circuit Not Plausible

Circuit/System Description

When the brake pedal is applied, the Body Control Module sends a serial data message to the Electronic Brake Control Module in reference to the brake pedal positions. The Electronic Brake Control Module compares the correlation between the brake pedal position and the amount of brake pressure it senses from the brake pressure sensor, which is internal to the Brake Pressure Modulator. It uses this information to control the vehicle during an stability event.

Conditions for Running the DTC

Ignition ON.

Conditions for Setting the DTC

* The Electronic Brake Control Module detects four accelerations from standstill to a vehicle speed greater 40 km/h (26 MPH) without any brake pedal position signal changes.

* The Electronic Brake Control Module detects the vehicle speed is greater than 20 km/h (13 MPH), the brake pedal is applied for six minutes, and brake pressure is less than 15 bar (218 PSI).

Conditions for Clearing the DTC

A current DTC clears when the diagnostic runs and passes.

Action Taken When the DTC Sets

No actions are taken

Diagnostic Aids

This DTC may set if the brake pedal is applied while accelerating.

Reference Information

Schematic Reference

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

Connector End View Reference

Component Connector End Views Outside Rearview Mirror - Driver

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

1. Ignition ON.

2. Apply and release the brake pedal. Verify the brake stop lamps operate properly.

• If the brake stop lamps do not operate properly
Refer to Symptoms - Lighting Symptoms - Lighting.

• If the brake stop lamps operate properly

3. Verify 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 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.

• 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 while applying and releasing the brake pedal.

• If the parameter does not change between Active and Inactive
Refer to Symptoms - Lighting Symptoms - Lighting.

• If the parameter changes between Active and Inactive

6. Refer to Diagnostic Aids.