Ignition Coil "G" Secondary Circuit
P2320 indicates a problem with the secondary circuit of ignition coil G, which controls spark timing for one of the engine's cylinders. This code sets when the PCM detects an electrical malfunction in the coil's control circuit, preventing proper ignition voltage from reaching the spark plug.
What You Might Notice
- Engine misfire or rough idle
- Diminished engine performance and power loss
- Reduced fuel efficiency
- Check Engine Light illuminated
- Possible fuel injector disabling for affected cylinder
Most Common Causes
- 1
Faulty Ignition Coil G
The ignition coil itself has failed or developed an internal short circuit in its secondary winding, preventing proper voltage delivery to the spark plug.
- 2
Damaged Coil Wiring or Connectors
The electrical harness or connector for ignition coil G is corroded, loose, or damaged, causing poor electrical contact or open circuit.
- 3
Engine Control Module (PCM) Issues
The PCM may have a faulty output circuit for ignition coil G control, though this is less common than coil failure.
- 4
Spark Plug or Cylinder Issues
A fouled spark plug, bad plug wire, or cylinder compression problem can cause the secondary circuit to work harder and trigger fault codes.
How to Diagnose It
- 1
Check Faulty Ignition Coil G — The ignition coil itself has failed or developed an internal short circuit in its secondary winding, preventing proper voltage delivery to the spark plug.
- 2
Check Damaged Coil Wiring or Connectors — The electrical harness or connector for ignition coil G is corroded, loose, or damaged, causing poor electrical contact or open circuit.
- 3
Check Engine Control Module (PCM) Issues — The PCM may have a faulty output circuit for ignition coil G control, though this is less common than coil failure.
- 4
Check Spark Plug or Cylinder Issues — A fouled spark plug, bad plug wire, or cylinder compression problem can cause the secondary circuit to work harder and trigger fault codes.
How to Fix It
- 1
Replace Ignition Coil G
Disconnect the coil connector and remove the coil pack from the cylinder head. Install a new ignition coil rated for your vehicle model and reconnect the electrical connector firmly.
- 2
Inspect and Repair Coil Wiring
Check the ignition coil harness and connector for corrosion, damage, or loose pins. Clean corroded connectors with electrical contact cleaner or replace damaged wiring sections.
- 3
Replace Spark Plug
Remove and inspect the spark plug in the affected cylinder. If fouled or worn, replace with the correct plug specification for your engine.
- 4
Have PCM Tested or Replaced
If ignition coil and wiring are confirmed good, have a professional test the PCM's ignition driver circuit. PCM replacement may be necessary but is typically a last resort.
Need a deeper diagnosis?
Search for related repair guides or browse by system.