For 1990-2009 cars only
Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC C0161 00: Antilock Brake System (ABS) Brake Switch CircuitCircuit/System Description
The electronic brake control module (EBCM) detects inputs from the brake pressure sensor, vehicle speed, and a serial data message from the 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. |
| • | Vehicle speed is greater than 16 km/h (10 mph). |
| • | Ignition voltage is greater than 9.5 volts. |
Conditions for Setting the DTC
| • | The vehicle speed is greater than 40 km/h (25 mph) and less than 3 km/h (2 mph) 4 times and the brake pedal signal does not show any change in state. |
| • | The vehicle speed is greater than 20 km/h (12 mph) and the brake pedal signal indicates an active state for continuously more than 6 minutes. |
Action Taken When the DTC Sets
The ABS/TCS/ESC remains functional.
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 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.
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Description and Operation Reference
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- With a scan tool observe the EBCM BPP signal parameter when applying and releasing the brake pedal. The readings should change between Applied and Released.
- Apply and release the brake pedal, verify stop lamps operate properly.
| ⇒ | If brake lamps do not operate properly, refer to Symptoms - Lighting Systems. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
