Test E: DTC C1222 - Wheel Speed Mismatch

Pinpoint Test E: DTC C1222 - Wheel Speed Mismatch
Refer to Vehicle/Diagrams, Dynamic Systems for schematic and connector information.

Normal Operation
The front wheel speed sensors are "active" sensors and generate a square wave signal that is sent to the ABS module. When the ignition is turned to the RUN position, the ABS module carries out a self-test to determine if the sensors are functional. Voltage and ground are supplied to the front wheel speed sensors from the ABS module along a pair of wires.

The rear wheel speed information is sent to the ABS module from the PCM over the high-speed controller area network (HS-CAN) bus. The PCM receives the information from the transmission output shaft speed (OSS) sensor.

Wheel speed sensor DTCs will automatically clear when a successful test drive is carried out. A successful test drive should include speeds above 32 km/h (20 mph) for at least 3 minutes and at least one ABS stop.
^ DTC C1222 Wheel Speed Mismatch - When the vehicle speed exceeds 20 km/h (12 mph), if the ABS module detects a difference between wheel speed sensor signals, DTC C1222 will be set. DTC C1222 can also be set by damaged tone rings, mismatched wheel and/or tire sizes, driving the vehicle on one or more underinflated tires, an incorrect axle ratio in the PCM or the wrong axle being installed on the vehicle.

This pinpoint test is intended to diagnose the following:
^ Mismatched tire sizes
^ Wheel speed sensor ring
^ Wheel speed sensor
^ OSS sensor
^ OSS sensor tone ring
^ Incorrect PCM configuration
^ Incorrect rear axle * HS-CAN bus
^ ABS module

E1-E4:

E5-E8:

E9-E11:

E11 (Continued)-E12: