C0161

C0161-ABS/TCS BRAKE SWITCH CIRCUIT MALFUNCTION





The normally-open stop lamp switch supplies battery voltage to the ECM when the brake pedal is pressed. The ECM sends a brake pedal applied serial data message to the Electronic Brake And Traction Control Module (EBTCM) and to the Transmission Control Module (TCM).

DTC PARAMETERS
DTC C0161 will be current if:
^ ECM detects an open or short to voltage in circuit 20.
^ Check for DTCs in the TCM and ECM. When DTC C0161 is current, ABS, TCS is not disabled.

DIAGNOSTIC AIDS
Using Scan tool, view the ABS data and monitor the brake switch while pressing on the brake pedal. If the switch changes according to brake pedal application, condition is intermittent.
Check the TCM and ECM for any DTCs If either the TCM or ECM has any DTCs current, follow the diagnosis.
Diagnose any communication DTCs first.
When diagnosing intermittent conditions, inspect wiring for the following:
^ Proper connection.
^ Backed-out terminals.
^ Broken connector locks.
^ Corrosion in connectors/terminals. Burned, chafed, or pinched wiring. Broken wire inside insulation. Loose components.