C1222: OBD-II code C1222 means the EBCM sees no signal from the right front wheel speed sensor — ABS and stability control are disabled while active.

Symptoms

• The ABS, traction control, and stability control warning lamps illuminate together, usually above 5 mph as the EBCM checks for wheel signals.
• Wheels can lock during hard braking and the brake pedal does not pulse during ABS events because interventions are unavailable.
• Vehicle stability control functions like electronic brake distribution and roll mitigation are disabled while the fault is active.

Common causes

• A failed right front wheel speed sensor — tip contaminated by debris or internal winding open — is the single most common cause.
• Excessive play in the right front wheel bearing or hub assembly lets the sensor-to-tone-ring gap vary too much for a stable signal.
• Damaged wiring at the strut, a corroded connector, or a rusted encoder ring on the CV joint will also drop the signal to zero.

What to do?

Scan the vehicle and check live wheel speed data during a slow road test. Rock the right front wheel by hand to test the hub bearing for play. Swap the left and right front sensors — if the fault moves to C1221, the sensor itself is bad. Inspect the harness where it clips to the strut for chafing and the connector for corrosion. Replace bearing, sensor, or repair wiring as indicated.