What does it mean?
P1339 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Camshaft Position Sensor (Bank 1) Open/Short to B+ .
Symptoms
- Engine cranks but will not start, or starts only after unusually long cranking
- Stalling shortly after start-up and repeated restarts
- Rough idle and misfire while the module runs on a substitute timing strategy
- Check engine light on with related crank and cam codes stored
- Loss of power and no variable valve timing operation
Likely causes
- Crankshaft and camshaft sensor connectors swapped or mis-pinned after repair work, since both plugs can be physically similar
- Open circuit in the cam sensor signal or supply wire, or a terminal backed out of the connector
- Short to battery voltage in the signal circuit where the harness runs beside a powered lead
- Failed camshaft position sensor with no output
- Corroded connector or a damaged harness section from heat and vibration on the cylinder head
- Incorrect replacement sensor with different output characteristics fitted at an earlier repair
- Module pin damage or an internal module input failure
How to fix it
- If the fault appeared right after service, first confirm the crank and cam sensors are plugged into the correct connectors and routed as the harness dictates
- Inspect both sensor connectors for backed-out terminals, corrosion and oil intrusion
- With the key on, verify supply voltage and ground at the cam sensor, then check the signal wire for unexpected battery voltage
- Test continuity from the sensor connector to the module pin on every wire in the circuit
- Compare the cam and crank signals in live data or on a scope during cranking; missing cam pulses with good crank pulses isolate the cam side
- Confirm the fitted sensor is the correct part for the engine before replacing anything else
- Replace the camshaft position sensor if it produces no output with proven-good wiring, then clear the code and retest a cold start