C0281

C0281 or C081

Circuit Description
The stoplamp switch is closed when the brake is released. Ignition voltage is supplied through the closed stoplamp switch to the EBCM. When the brake is applied, the switch is open and the signal to the EBCM is low.

Conditions for Running the DTC
^ The ignition is ON.
^ The vehicle experiences an ABS event involving all 3 brake circuits OR:
^ The ignition is ON.
^ The vehicle is moving at a speed of less than 56 km/h (35 mph) when the EBCM completes the ABS bulb check.
^ The vehicle reaches a speed of greater than 56 km/h (35 mph) after the above criteria are met and then comes to a stop.

Conditions for Setting the DTC
Either of the following conditions will set DTC C0281:
^ The EBCM detects that the brake is released during an ABS event involving all 3 brake circuits.
^ The EBCM detects that the brake is applied for the entire time that the ignition is ON.

Conditions for Clearing the DTC
^ The condition(s) responsible for setting the DTC is no longer present.
^ A scan tool is, Used in order to clear the DTC.

Diagnostic Aids
Thoroughly inspect connections or circuitry that may cause an intermittent malfunction. Refer to Testing for Intermittent and Poor Connections, Connector Repairs and Wiring Repairs.

Test Description

The numbers below refer to the step numbers on the diagnostic table:
4. This step tests for a shorted stoplamp switch.
5. This step tests for an open stoplamp switch.
12. If the system is functioning properly, the scan tool displays On when the brake is applied and Off when the brake is released.