Diagnostic Instructions
DTC Descriptor
DTC C0161 00: Antilock Brake System (ABS) Brake Switch Circuit
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 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
The vehicle speed is greater than 16 km/h (10 mph).
Conditions for Setting the DTC
One of the following conditions exists:
| • | The EBCM detects the brake pedal signal is continuously Active for 4.2 minutes when driving faster than 20 kph (13 mph). |
| • | The EBCM detects the brake pressure sensor signal indicating a pressure increase but the brake light switch signal is not changing. |
| • | The EBCM detects 4 times, the vehicle accelerating to speeds above 40 kph (25 mph) and decelerating down to speeds below 3 kph (2mph) and no change in the brake light switch signal. |
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
Component Connector End Views
Description and Operation Reference
ABS Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Verify DTC C0277 or C0890 is not set.
