What it means
The generator position sensor B circuit signal is above the expected level. This indicates a high signal in that circuit; the cause depends on the vehicle.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
The generator position sensor's B circuit sends rotor-position information to the drive control system. P0C6C sets when circuit B rises above its expected electrical level, commonly because the signal wire is shorted to battery positive, the sensor is open, or corrosion disrupts the connection.
Common causes
Most likely first.
- Signal wire shorted to B+
- Open sensor
- Connector pins corroded - high contact resistance
Symptoms
- Hybrid or EV system warning light on
- Reduced power or limited vehicle operation
How to diagnose it
- Review freeze-frame and live data to confirm circuit B is reporting a high signal and note any simultaneous hybrid or generator codes.
- Inspect the circuit B harness and connector for contact with a power wire, damaged insulation, loose pins, or corrosion, using the manufacturer's power-down precautions.
- Check circuit B supply, ground, and signal connections against the wiring diagram and manufacturer's specification.
- With the circuit isolated as directed, test the signal wire for a short to battery positive and check connector continuity.
- If the harness and connector pass, test the circuit B sensor for an open condition using the manufacturer's procedure.
Common fixes
- Repair circuit B signal wiring shorted to battery positive.
- Restore or replace corroded, loose, or damaged connector terminals.
- Replace the circuit B position sensor if it tests open.
- Verify the signal is within the manufacturer's specification and confirm the code does not return.
Can I keep driving?
The vehicle may limit drive power when circuit B cannot provide valid position information. Avoid journeys where reduced power could create a hazard, and stop safely if a hybrid warning or power limitation develops.
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.