Code Description
WARNING: This page is about a different car, the 2006 Ford Pickup, 2006 Ford F550 Super Duty, 2006 Ford F450 Super Duty, and 2006 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
DTC C1222 - Wheel Speed Mismatch, DTCs C1233 (LF), C1234 (RF), C1236 (Rear) - Wheel Speed Sensor Signal Fault
The wheel speed sensor and sensor ring generate a square wave signal to the anti-lock brake system (ABS) module that is proportional to wheel speed. The ABS module compares wheel speed inputs from all wheel speed sensors to determine an impending wheel lockup. Incorrect tire size can set these DTCs as well.