C0161

DTC C0161

Diagnostic Instructions

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



DTC Descriptor
DTC C0161 5A
- TCS Brake Switch Circuit Plausibility Failure




Circuit/System Description

The brake pedal position (BPP) sensor is an input to the body control module (BCM). The BCM then sends a serial data message to the electronic brake control module (EBCM) and other electronic control modules. The BPP sensor is a potentiometer type sensor with a 5-volt reference circuit and a low reference circuit. The IPM supplies the 5-volt reference to the BPP.


Conditions for Running the DTC

* The ignition is ON.
* The vehicle speed is greater than 16 km/h (10 mph).
* The ignition voltage is greater than 8 volts.



Conditions for Setting the DTC

* The brake pedal is sensed as applied during moderate to high vehicle acceleration.
* With the vehicle decelerating, the brake pedal is sensed as released and the master cylinder pressure is greater than 90 psi.



Action Taken When the DTC Sets

* The EBCM disables the Traction Control System (TCS) and Vehicle Stability Enhancement System (VSES) for the duration of the ignition cycle.
* The Traction Control indicator turns ON.
* The driver information center (DIC) displays Service Stability System message.
* The Antilock Brake System (ABS) remains functional.



Conditions for Clearing the MIL/DTC

* The condition for the DTC is no longer present and the DTC is cleared with a scan tool.
* The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.



Diagnostic Aids

The DTC C0161 00 can be set if the vehicle has been driven with the brake applied during acceleration. Verify that the brake pedal position sensor is properly calibrated. Refer to DTC U1826 or U1827 (U1826) .


Reference Information
Schematic Reference

Antilock Brake System Schematics ([1][2]Antilock Brakes / Traction Control Systems)
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 (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)



Scan Tool Reference

Control Module References (Programming and Relearning)


Circuit/System Verification

With the ignition ON, use a scan tool to display DTCs for the body control module (BCM).

If DTC C0277 is present, refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code Descriptions) .


If no DTCs are present, go to Diagnostic Aids.



Repair Instructions

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