Test H: DTC C1233 (LF), C1234 (RF), C1235 (RR) & C1236 (LR) - Wheel Speed Input Signal Missing

Check Suspect Wheel Speed Sensor

Inspect suspect wheel sensor mounting. Ensure wheel speed sensor is clean and free of excessive dirt buildup and metal obstructions. Ensure wheel speed sensor is not damaged. Repair or replace wheel speed sensor if necessary. If no problems are found, go to next step.

Check Suspect Wheel Speed Sensor Indicator

Ensure suspect wheel speed sensor indicator is free from corrosion, nicks, bridged or damaged teeth. Check for correct mounting and alignment with wheel speed sensor. Ensure air gap is less than .04" (1 mm). Ensure there is no excessive wheel bearing end play. If any problems are found, replace wheel speed sensor indicator. Clear codes and repeat self-test. If no problems are found, go to next step.

Check Suspect Wheel Speed Sensor PIDs

Turn ignition on and clear codes. Turn ignition off. Test drive vehicle with an assistant and monitor ABS control module PIDs LF_WSPD, RF_WSPD, LR_WSPD, and RR_WSPD while driving at various speeds for at least 10 miles. If ABS control module PIDs are reading approximately the same at all times, clear codes and repeat self-test. If DTC C1233, C1234, C1235 or C1236 is retrieved, replace ECU. Repeat self-test. If no DTCs are retrieved, system is operating normally. If ABS control module PIDs are not reading approximately the same at all times, replace wheel speed sensor. Clear codes and repeat self test.