C00A3 code meaning
Driveline Control Module Rear Differential Unit A Control Circuit Driver
What C00A3 means
C00A3 points to the driver stage inside the driveline module that powers actuator A of the rear differential unit, not to the actuator itself. The module's own transistor monitoring reports something wrong at that output. A Mitsubishi Electric patent illustrates the principle on an electromagnetic clutch: a PWM high-side and a low-side transistor feed the coil, the filtered terminal voltages are checked with the selector in P or N, and if they deviate from normal both transistors are switched off so the clutch opens. Modern H-bridge drivers such as TI's DRV8873-Q1 separately flag overcurrent, short to battery or ground, open load and overtemperature. On hydraulically actuated twin-clutch units, a dedicated ECU drives solenoid valves instead. No manufacturer publishes a C00A3 case; actuator A's own codes are C0095 and C0096.
C00A3 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyHard
- Typical labor0.5 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of C00A3
- Rear clutch released, AWD inactive
- AWD warning in the instrument cluster
Common causes of C00A3
- Most likelyShort to ground or battery in the actuator A supply lines
- PossibleActuator A motor or coil drawing excessive current (binding, winding short)
- Less likelyOutput stage in the module overheated or defective
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Driveline moduleRear diff actuator a
What each part of C00A3 means
| C | Chassis system: brakes, ABS, steering and suspension. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| A3 | The exact fault in that area. |
What to do next
- Note C00A3 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about C00A3
What does C00A3 mean?
C00A3 means "Driveline Control Module Rear Differential Unit A Control Circuit Driver". C00A3 points to the driver stage inside the driveline module that powers actuator A of the rear differential unit, not to the actuator itself. It is a generic code, so it means the same on every make.
Is it safe to drive with C00A3?
Drive gently and only to a workshop. With C00A3 the car can go into limp mode (reduced power) to protect itself.
Will C00A3 fail an emissions test?
C00A3 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is C00A3 to fix?
Difficulty: hard. A typical repair takes 0.5 to 4 hours of work. This is a job for a workshop.
Will C00A3 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.