What Does Code P003F Mean P003F OBD2 specifically refers to the camshaft (cam) timing. In this case, if the cam timing is over-retarded, the engine light will be illluminated and the code will be set. engine code P003FP003F fixobd P003Fdtc P003Fobd code P003Fobd2 P003FP003F car codediagnostic code P003Fcar code P003Fcheck engine code P003Ffehlercode P003FP003F fiatcodigo P003Fcodigo falla P003FP003F kody błędówcodigo de falla P003FPossible symptoms Engine Light ON (or Service Engine Soon Warning Light) Possible causes Faulty Camshaft Position Sensor Camshaft Position Sensor harness is open or shorted Camshaft Position Sensor circuit poor electrical connection P003F OBDII Repair : The sensors receive a 5 volt reference signal from the PCM. As pressure readings change, the sensor varies the voltage and the computer reads that to determine input. In the case of a broken wire, the sensor never sees the voltage and the computer assumes a major fault. So if you get this P003F code, first check to make sure you're getting a good 5 volt reference signal at the sensor. Disconnected, dirty or fouled spark plugs are common causes for engines that won't start. Spark plugs typically need to be replaced every season or 25 hours of use. You should also check that the spark plug gap is set properly. If your spark plugs look good, problems with your ignition system can also preventing a spark. These can range from a faulty spark plug lead, shorted kill switch or flywheel key damage.