P1397 – Ignition Coil Driver Undercurrent
Want to confirm the real cause of this fault code?
A high‑quality OBD2 scanner gives you live data, fuel trims, sensor readings and freeze‑frame information — exactly what you need to verify the root cause of this code with confidence.
Symptoms
- Weak spark
- Misfire
- Poor acceleration
Causes
- Open circuit
- Damaged wiring
- Faulty coil
Diagnosis
- Measure coil current
- Inspect wiring
- Check coil resistance
Repair
- Replace coil
- Repair wiring
- Repair ECU driver