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C0099: 4WD/AWD Rear Differential Unit Actuator A Position Sensor A

System
Chassis

What Does C0099 Mean?

C0099 is a diagnostic trouble code indicating: 4WD/AWD Rear Differential Unit Actuator A Position Sensor A. This code relates to the chassis system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

What To Do Next

  1. 1
    Find your vehicle above

    Click your make and model for real owner reports and common causes specific to your vehicle.

  2. 2
    Check for recalls

    Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.

  3. 3
    Get a professional diagnosis

    A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

Related Codes

C0094 4WD/AWD Rear Differential Unit Temperature Sensor C0095 4WD/AWD Rear Differential Unit Actuator A C0096 4WD/AWD Rear Differential Unit Actuator A Data C0097 4WD/AWD Rear Differential Unit Actuator B C0098 4WD/AWD Rear Differential Unit Actuator B Data C0001 TCS Control Channel A Valve 1 C0002 TCS Control Channel A Valve 2 C0003 TCS Control Channel B Valve 1