What it means
The driveline control module monitors its driver for the power transfer unit control circuit and sets this code when the driver detects a fault controlling that circuit.
How it works
The driveline control module uses an electronic driver to command the power transfer unit (PTU), which helps route drive to the other axle. It monitors the PTU control circuit for an electrical fault while commanding it. An open, short, or driver fault can set C00A2 and may leave AWD or 4WD limited.
Common causes
Most likely first.
- Open or short in the PTU control circuit
- Damaged wiring or connector
- Power or ground fault
- Driveline control module driver fault
Symptoms
- AWD or 4WD warning
- AWD may be unavailable or limited
How to diagnose it
- Read driveline-module codes and freeze-frame data first to see when the PTU circuit fault occurred and whether related power or communication faults are present.
- Check the AWD or 4WD live data for the PTU command and status, if available, to see whether the module is requesting a change when the fault appears.
- Inspect the PTU connector and its harness for corrosion, loose pins, chafing, or damage, paying particular attention to routing near the driveline.
- Check the driveline control module and PTU power and ground connections for looseness, corrosion, or voltage drop under the manufacturer's test procedure.
- With the vehicle wiring information, test the PTU control circuit for opens or shorts and compare results with the manufacturer's specification before suspecting the module driver.
Common fixes
- Clean and secure a loose or corroded PTU connector.
- Repair damaged wiring or terminals in the PTU control circuit.
- Repair a verified power or ground fault to the driveline control module or PTU.
- Replace the PTU only if testing identifies an internal PTU fault.
- Replace or reprogram the driveline control module only after its driver is confirmed faulty and circuit faults are ruled out.
Can I keep driving?
AWD or 4WD may be unavailable, so avoid relying on it for slippery or difficult terrain and drive cautiously if the vehicle behaves normally in two-wheel drive. Stop if you notice binding, unusual driveline noise, or loss of drive.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.