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: ABS/TCS Brake Switch CircuitCircuit/System Description
The body control module (BCM) illuminates the stop lamps by applying battery positive voltage to the stop lamp supply voltage circuit. The electronic brake control module (EBCM) receives a voltage input from the stop lamp supply voltage circuit to determine if the brake pedal is applied.
Conditions for Running the DTC
| • | The ignition is ON. |
| • | The vehicle speed is greater than 20 km/h (12 mph). |
Conditions for Setting the DTC
| • | The brake pedal is sensed as applied for 6 minutes. |
| • | The vehicle speed is greater than 20 km/h (12 mph). |
| • | The EBCM does not receive a signal change from the stop lamp supply voltage circuit. |
| • | Vehicle speed exceeds 40 km/h (25 mph) in four cycles, and decelerates to under 3 km/h (2 mph). |
Action Taken When the DTC Sets
The ABS remains functional.
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present. |
| • | The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
Diagnostic Aids
The DTC C0161 can be set if the vehicle has been driven with the brake applied during acceleration. Also inspect the brake pedal switch and connector for proper operation.
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Ignition On, observe the scan tool EBCM Stop Lamp parameter. The reading should be Released and change between Applied and Released when pressing and releasing the brake pedal, the stop lamps should turn on and off.
| ⇒ | If not within the specified value, refer to Stop Lamps Malfunction. If the circuits test normal, replace the EBCM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for EBCM replacement, setup and programming
