What does it mean?
P1376 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: IC Module Ignition Ground Circuit Malfunction .
Symptoms
- MIL on, sometimes with a no-start or intermittent stalling
- Misfire, rough running and backfiring
- Hard hot restart after a short shutdown
- Erratic tachometer behaviour
- Loss of power under load and an unstable idle
Likely causes
- Loose, corroded or paint covered ground bolt and eyelet at the module
- Broken or high resistance ground wire inside the harness
- Corrosion on the ground terminal inside the module connector
- Module not seated properly on its mounting surface where the case carries the ground
- Failed ignition control module with an internally open ground path
- Corroded engine to body ground strap shifting the ground reference
- Damaged shared PCM ground circuit
How to fix it
- Perform a voltage drop test on the module ground while cranking, the reading must stay very low
- Remove, clean and retorque the ground bolt and clean the mating surface down to bare metal
- Inspect the module connector for green corrosion and burnt or discoloured terminals
- Check the engine to chassis ground strap and its attachment points
- Compare the module ground reference against the PCM ground while the engine runs
- Repair or replace the ground wire and pigtail if resistance is high
- Replace the ignition control module only once the external ground path has been proven good