C1224

Circuit Description
The speed sensor used on this vehicle is a multiple pole magnetic pickup. This sensor produces an AC signal when a toothed ring passes the wheel speed sensor. The EBCM uses the frequency to calculate the wheel speed.

Conditions for Running the DTC
^ DTCs C1232-C1235 are not set.
^ The brake pedal is not pressed.
^ The vehicle is not in an ABS stop.

Conditions for Setting the DTC
^ The right rear wheel speed is equal to zero.
^ The other wheel speeds are greater than 8 km/h (5 mph).
^ The difference between the other three wheel speed sensors is less than 11 km/h (6.8 mph)
^ The above conditions are present for 2.5 seconds.

Action Taken When the DTC Sets
^ The ABS/TCS disables.
^ The EBCM turns on the ABS and the TRAC OFF (if equipped) indicator(s).

Conditions for Clearing the DTC
^ Condition for DTC is no longer present and scan tool clear DTC function is used.
^ 100 ignition cycles have passed with no DTC(s) detected.

Diagnostic Aids
^ It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction.
^ An intermittent malfunction can be caused by poor connections, broken insulation, or a wire that is broken inside the insulation.
^ If an intermittent malfunction exists refer to Testing for Intermittent and Poor Connections.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
4. This step tests the wheel speed sensor for the proper resistance value.
5. This step ensures that the wheel speed sensor generates the proper voltage.
7. This step tests whether the wheel speed sensor circuits are shorted together.