Ignition Coil "H" Secondary Circuit
P2323 indicates a problem with the ignition coil H secondary circuit, meaning the PCM detected an electrical fault in the coil pack or its wiring that prevents proper spark generation for that cylinder. This causes the fuel injector for that cylinder to be disabled by the PCM as a protective measure.
What You Might Notice
- Engine misfire or rough idle
- Diminished engine performance and power loss
- Reduced fuel efficiency
- Check engine light illuminated
- Potential secondary trouble codes for other cylinders
Most Common Causes
- 1
Faulty ignition coil
The ignition coil pack H has internally failed or lost continuity. This is the most common cause and typically requires coil replacement.
- 2
Damaged coil wiring or connectors
Corrosion, loose connections, or damaged wires in the secondary circuit prevent proper voltage transmission to the spark plug.
- 3
Spark plug or spark plug wire issues
A worn spark plug or damaged secondary wire creates excessive resistance in the circuit, triggering the fault code.
- 4
PCM or ECU malfunction
Rarely, a faulty engine control module may incorrectly report a secondary circuit fault when the coil itself is functional.
How to Diagnose It
- 1
Check Faulty ignition coil — The ignition coil pack H has internally failed or lost continuity. This is the most common cause and typically requires coil replacement.
- 2
Check Damaged coil wiring or connectors — Corrosion, loose connections, or damaged wires in the secondary circuit prevent proper voltage transmission to the spark plug.
- 3
Check Spark plug or spark plug wire issues — A worn spark plug or damaged secondary wire creates excessive resistance in the circuit, triggering the fault code.
- 4
Check PCM or ECU malfunction — Rarely, a faulty engine control module may incorrectly report a secondary circuit fault when the coil itself is functional.
How to Fix It
- 1
Replace ignition coil pack H
Remove and replace the faulty ignition coil for cylinder H. Disconnect the electrical connector and mounting bolts, then install a new coil and reconnect all components. Clear the code after repair.
- 2
Inspect and repair wiring and connectors
Check the secondary circuit wiring from the coil to the spark plug for damage, corrosion, or loose connections. Repair, clean, or resecure connections as needed.
- 3
Replace spark plug and secondary wire
Remove the old spark plug and wire for cylinder H, then install new components with proper gap specification. Ensure secure connections at both the coil and plug.
- 4
Perform PCM diagnostics and reset
Use a professional diagnostic scanner to verify no PCM faults exist, then clear the trouble code. Perform a test drive to confirm the code does not return.
Need a deeper diagnosis?
Search for related repair guides or browse by system.