Diagnostic Instructions
DTC Descriptors
DTC C0161 00: Brake Switch Circuit Malfunction
DTC C0161 71: Brake Switch Invalid Signal
Diagnostic Fault Information
Circuit
| Short to Ground
| Open/High Resistance
| Short to Voltage
| Signal Performance
|
Antilock Brake System (ABS) Brake Switch/Sensor Circuit
| C0161 00
| C0161 00
| C0161 00
| -
|
Circuit/System Description
The brake switch informs the electronic brake control module (EBCM) when the
brake is depressed. The brake switch is normally closed, supplying 12 volts to the
EBCM when the brake is released. When the brake pedal is pressed, voltage on the torque
converter clutch (TCC) brake switch signal circuit is 0 volts.
Conditions for Running the DTC
| • | The vehicle speed is greater than 16 km/h (10 mph). |
| • | The ignition voltage is greater than 8 volts. |
Conditions for Setting the DTC
DTC C0161
| • | The brake pedal is sensed as applied. |
| • | The vehicle speed is greater than 40 km/h (25 mph). |
| • | The vehicles acceleration exceeds 8 km/h per second (5 mph
per second). |
| • | Brake pedal is not applied. |
| • | Master cylinder pressure is greater than 150 psi. |
| • | The vehicle speed is greater than 24 km/h (14 mph). |
| • | The vehicles deceleration exceeds 11.5 km/h per second (7 mph
per second). |
Action Taken When the DTC Sets
| • | The EBCM disables the Antilock Brake System (ABS)/Traction Control System
(TCS)/Electronic Stability Control (ESP)/Electronic Brake Distribution (EBD) for the
duration of the ignition cycle. |
| • | The multi function display (MFD) displays the ABS Fault message. |
| • | The multi function display (MFD) displays the Traction Ctrl Off message. |
| • | The multi function display (MFD) displays the Stability Ctrl Off message. |
Conditions for Clearing the DTC
| • | The condition for setting 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. |
| • | The DTC can be cleared using a scan tool. |
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
Electrical Information Reference
Scan Tool Reference
Control Module References
Circuit/System Verification
With scan tool installed, clear the DTCs then drive the vehicle in a straight
line at a speed greater than 20 km/h (13 mph). If the DTC did not set
as a current DTC see diagnostic aids.
Circuit/System Testing
Important: If DTC B3445 is set to current diagnose it
first. Refer to
DTC B3445
.
- Apply and release brake pedal. Verify brake lamps operate correctly. If
brake lamps do not operate correctly, refer to
Symptoms - Lighting Systems
.
- Test the stop lamp supply voltage circuit for a short to voltage, short
to ground, an open or high resistance.
| ⇒ | If the stop lamp circuit tests normal, replace the brake modulator assembly/EBCM. |
Repair Instructions
