P0C6A

What it means

P0C6A is the generic code for a range or performance fault in the generator position sensor circuit B. This sensor reports the rotor position of the generator (the motor-generator used in hybrid and electric drive systems) to the control unit. The control unit has seen a signal from circuit B that is implausible, out of range or inconsistent with other position or speed data, so it has set the code. Exact sensor type and layout depend on the vehicle and drive system.

Symptoms

• Hybrid system or malfunction warning light on
• Reduced power or the car going into limp mode
• Engine will not start or stalls unexpectedly on a hybrid
• Rough running, hesitation or vibration when the generator is in use
• Poor fuel economy or the hybrid battery not charging properly
• Hybrid drive unavailable or reduced

Possible causes

• Damaged, chafed or corroded wiring or connectors in the generator position sensor circuit Blikely
• Faulty generator position sensor (resolver or similar) giving an erratic or out-of-range signallikely
• Poor sensor mounting, incorrect air gap or contamination affecting the signalpossible
• Interference on the signal from damaged shielding or a poor earthpossible
• Fault in the hybrid or inverter control unit that processes the sensor signalrare
• Mechanical damage to the generator or its rotor affecting the position readingrare

How to diagnose

1. Read all stored and pending codes and note any related generator, motor or inverter codes.
2. Review freeze frame data to see speed, load and drive mode when the code set.
3. Visually inspect the sensor wiring and connectors for chafing, heat damage, water ingress and corrosion, following the high-voltage safety procedure for the vehicle.
4. Check the live position and speed data for the generator and compare it with the engine or motor speed for plausibility.
5. Check the sensor circuit resistance, continuity and shorts to earth or supply against the manufacturer's specification, with the system made safe.
6. Check the sensor mounting, shielding and earth connections for security and condition.
7. Clear the code and road test to see if it returns, watching the live data for dropouts.
8. If the wiring and sensor test fine, check for software updates or known faults for that model and consider control unit testing.

How to fix

• Repair or replace damaged wiring and clean or replace corroded connectors.
• Replace the generator position sensor if it tests faulty or out of specification.
• Refit or secure the sensor correctly and restore the correct mounting position or air gap where it is adjustable.
• Repair shielding or earth connections that are causing signal interference.
• Repair or replace the generator assembly if there is mechanical damage.
• Replace or reprogram the control unit only after the circuit and sensor are proven good and the manufacturer confirms an update or fault.

Can I keep driving?

Nearby codes

• P0C69GenericGenerator Position Sensor Circuit B
• P0C6BGenericGenerator Position Sensor Circuit B Low