Fault code P0338 – a step-by-step guide to diagnosing and fixing it

Error code P0338 is displayed and the check engine light is on - what does this mean?

DTC P0338 is triggered by the OBD/EOBD system when a problem is detected with the crankshaft position sensor A (crankshaft position sensor) in the circuit. This trouble code indicates a low voltage level in the sensor signal, which can affect the engine control. For various manufacturers, this fault code may also be referred to as "Crankshaft Position Sensor A Circuit Low Input".

What causes can this fault code have?

• Defective crankshaft position sensor
• Damaged or corroded sensor cable
• Loose or defective plug connections on the sensor
• Short circuit to ground in the wiring harness
• Dirty or damaged sensor ring on the crankshaft
• Defective engine control unit (ECU)
• Excessive air gap between sensor and encoder wheel
• Mechanical damage to the crankshaft area

What symptoms occur in parallel with fault code P0338?

• Starting problems: The vehicle is difficult or impossible to start
• Engine misfires: Irregular engine running and jerky driving
• Loss of power: Noticeable reduction in engine power
• Check engine light: Permanent display of the check engine light
• Engine stalling: Engine suddenly stops while driving
• Ignition problems: Misfiring and rough idling

How can the problem with error code P0338 be rectified?

• Repairing EOBD error code P0338 requires a systematic approach to identifying and eliminating the cause.
• Replace the crankshaft position sensor completely and set the correct air gap of 0.5-1.5mm to the encoder wheel
• Check the entire wiring harness from the sensor to the ECU, repair or replace damaged cables and clean all plug connections
• Check the sensor ring on the crankshaft for dirt, cracks or missing teeth and replace if damaged
• Disconnect electrical connections on the sensor, clean with contact spray and reconnect firmly
• Use the OBD diagnostic device to clear the code and then carry out a test drive to check the repair
• If DTC P0338 occurs repeatedly, have the engine control unit checked at a specialist workshop and replaced if necessary