P0C65

What it means

P0C65 is the generic code for a range or performance fault on the generator position sensor circuit A. This sensor tells the hybrid or electric drive control unit the rotor angle of the generator motor so it can time the current correctly. The control unit has seen a signal that is implausible, out of range or does not agree with other speed or position data, though the circuit is not necessarily open or shorted.

Symptoms

• Hybrid system warning light or malfunction indicator lamp on
• Reduced power or the car going into a limp-home mode
• Engine will not start or hybrid system will not enter ready mode
• Rough running, vibration or hesitation when the engine starts or stops
• Poor fuel economy or the engine running more than normal
• Intermittent loss of drive or the system shutting down

Possible causes

• Poor connection or damaged wiring in the generator position sensor circuit (corrosion, chafing, loose terminals, signal noise)likely
• Faulty generator position sensor (resolver or equivalent), or the sensor out of alignment with the rotorpossible
• Damage or contamination at the generator housing connector, such as coolant or oil ingresspossible
• Electrical interference from high-voltage cables or poor shielding or earthing of the sensor wiringpossible
• Mechanical fault in the generator, such as a bearing problem or rotor damage affecting the signalrare
• Fault within the inverter or hybrid control unit, or outdated softwarerare

How to diagnose

1. Read all stored and pending codes and the freeze frame data, noting speed, temperature and whether the system was in ready mode when the fault set.
2. Check for related codes covering other position sensors, the generator, motor or inverter, and deal with any supply or communication faults first.
3. Visually inspect the sensor wiring and connectors for chafing, corrosion, moisture, bent pins and poor terminal tension. Do not touch high-voltage parts or orange cabling unless trained and the system is isolated.
4. Wiggle-test the harness with live data on a scan tool, watching the generator position or speed signal for dropouts or spikes.
5. Test the circuit's continuity, resistance to earth and shielding against the manufacturer's figures, with the system safely isolated.
6. Check the sensor's coil resistance or signal pattern against specification, using an oscilloscope if the procedure calls for it. Values and method depend on the make and model.
7. Inspect the generator for leaks, bearing noise or mechanical damage, and check sensor mounting and alignment.
8. Check for software updates or technical bulletins for the model before replacing expensive hybrid components.

How to fix

• Repair or replace damaged wiring, and clean or replace corroded or loose connectors.
• Replace the generator position sensor and set it up as the manufacturer specifies.
• Fix any coolant or oil leak that has contaminated the sensor or connector, and replace affected parts.
• Restore shielding and earth connections that are damaged or missing.
• Repair or replace the generator if there is mechanical damage, following manufacturer procedures.
• Update the control unit software only if a known fault or bulletin applies, or replace the unit if testing proves it faulty.

Can I keep driving?

Nearby codes

• P0C64GenericGenerator Position Sensor Circuit A
• P0C66GenericGenerator Position Sensor Circuit A Low