Engine

P03F6 — Camshaft Position Actuator Sensor "C" Circuit Fault, Bank 1

Severity: medium Drive with care, to a shop

What P03F6 means

P03F6 is a manufacturer-specific code. Most often it is read as a fault in the circuit or signal of the camshaft position actuator sensor "C" on bank 1. The ECU compares the commanded and actual camshaft angle, and logs the code when they disagree or the sensor signal is implausible. Some scan tools show it alongside misfire codes, so confirm the definition for your specific make and model.

Symptoms

  • Check engine light on
  • Rough idle
  • Hesitation on acceleration
  • Reduced power
  • Poor fuel economy
  • Possible misfire feel

Possible causes

  1. Faulty camshaft position actuator sensor "C" (bank 1)
  2. Damaged, corroded or loose wiring or connector at the sensor or actuator
  3. Failed VVT solenoid (oil control valve)
  4. Low oil level or pressure, or old, dirty oil
  5. Faulty camshaft phaser (adjuster)
  6. Stretched timing chain or incorrect cam timing
  7. ECU software problem or internal fault (rare)

How to diagnose

  1. Read all codes and freeze frame data, and look for related misfire or cam timing codes
  2. Check oil level and condition; change oil and filter if needed
  3. Inspect the sensor and VVT solenoid wiring and connectors for chafing, oil contamination, corrosion and a secure fit
  4. Compare specified and actual cam angle in live data
  5. Test power, ground and signal at the sensor with a multimeter or scope, following the manufacturer's wiring diagram
  6. Command the VVT solenoid with a scan tool and confirm the cam angle responds
  7. If the deviation persists, check timing marks and timing chain condition
  8. Check for an ECU software update for your model

Common fixes

  • Replace the camshaft position actuator sensor
  • Repair the wiring harness or connector
  • Replace or clean the VVT solenoid
  • Change the oil and filter and fix the cause of low oil pressure
  • Replace the camshaft phaser or the timing chain and tensioners
  • Reflash or replace the ECU if confirmed faulty

Questions and answers

What does P03F6 mean?

It is a manufacturer-specific code. It usually points to a problem in the circuit or signal of the camshaft position actuator sensor "C" on bank 1. Some scan tools display it like a misfire code, so confirm the definition for your vehicle.

Can I drive with P03F6?

Short, light driving to a repair shop is usually fine. If the engine runs rough or the check engine light flashes, stop driving to avoid damaging the catalytic converter or engine.

Where should I start diagnosing P03F6?

Check oil level and condition first, then inspect the wiring and connectors of the sensor and VVT solenoid. After that, compare specified and actual cam angle in live data.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.