C009F4WD/AWD Rear Differential Unit Actuator B Position Sensor C
- Generic OBD-II code · Chassis
- Can trigger limp mode
- How the car detects it
- Third position channel C of actuator B in the rear differential unit is the subject of this code. Its absence is noticed because the remaining channels A and B still produce transitions that C should follow. Woodward's patent shows the method: after an invalid combination the controller waits for the next one, and the sensor whose output did not move in between is the failed one; the motor can then be driven with a substitute third signal. In a rear unit such as BorgWarner's electro-hydraulic coupling, whose brushless actuator motor carries its own electronics, this monitoring sits next to the motor, so the fault may be reported over the bus by an integrated controller. No manufacturer bulletin mentions C009F. Repairs usually mean wiring checks first, then a new actuator motor.
- What you may notice
- AWD warning lamp
- Rear torque split or locking function deactivated
- Likely causes
- LikelyOpen or high-resistance channel C line of actuator B
- PossibleHall element C of actuator B defective
- RareFault in electronics integrated in the actuator motor
- Repair
- Hard · Usually a job for a workshop.Typical cost: €80 – €1,200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.