What it means
The generator position sensor A circuit signal is intermittent or erratic. 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 A circuit reports rotor position to the drive control system. P0C68 sets when that signal drops out or varies unpredictably rather than remaining stable, often because of a connector that is not seated, a noisy ground reference, or contact that opens with vibration.
Common causes
Most likely first.
- Connector not seated
- Noisy ground reference
- Connector with intermittent contact under vibration
Symptoms
- Hybrid or EV system warning light on
- Reduced power or limited vehicle operation
How to diagnose it
- Check freeze-frame and live data for circuit A and note whether the signal fault occurred during vibration, acceleration, or a change in operating state.
- Inspect the circuit A connector for incomplete seating, damaged locks, corrosion, or pins that can move, and inspect the harness for chafing or strain.
- Check circuit A ground and reference connections against the manufacturer's wiring information for looseness or contamination.
- Monitor circuit A signal while gently moving the accessible harness and connector as allowed by the manufacturer's procedure, looking for dropouts.
- If the connection remains stable, test the circuit A sensor and wiring for intermittent opens or noise using the manufacturer's diagnostic procedure.
Common fixes
- Fully seat and secure the circuit A connector.
- Repair loose, corroded, or damaged circuit A terminals and wiring.
- Restore the circuit A ground or reference connection if it is unstable.
- Replace the sensor if its output remains intermittent after the harness and connections are repaired.
Can I keep driving?
An intermittent position signal can cause warning lights and sudden limited operation. Avoid demanding driving and stop safely if power becomes unpredictable; continued use may lead to loss of normal drive power.
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.