Diagnostic Instructions
DTC Descriptor
DTC C0161 5A : Antilock Brake System (ABS) Brake Switch Circuit Plausibility Failure
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 voltage is greater than 10 volts. |
Conditions for Setting the DTC
• | The EBCM detects the vehicle speed greater than 21 km/h (13 mph), the brake pedal is Applied for 1 minute , and brake pressure is not increasing. |
• | The EBCM detects brake pedal is Released and the vehicle speed is decreasing while the brake pressure is increasing. |
Actions Taken when the DTC Sets
• | The EBCM disables the traction control and StabiliTrak for the duration of the ignition cycle. |
• | A DIC message and/or a warning indicator may be displayed. |
Conditions for Clearing the DTC
• | The condition for the DTC is no longer present. |
• | The EBCM clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles. |
Diagnostic Aids
The DTC C0161 00 can be set if the brake pedal is applied while accelerating.
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
ABS Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Verify that DTC C0277, C0297, or B3445 is not set.
- Ignition ON, observe the scan tool EBCM BPP parameter while applying and releasing the brake pedal. The reading should change between Applied and Released.
⇒ | If the parameter does not change between applied and release, replace the EBCM. |
- Replace the BPMV.
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.