Ignition Coil "K" Primary Control Circuit High
P2331 indicates the ignition coil K primary control circuit is reading a higher voltage than expected, preventing proper spark generation for that cylinder. This means the engine control module cannot adequately drive the ignition coil, causing the cylinder to misfire.
What You Might Notice
- Engine misfire on cylinder K
- Reduced engine performance and power
- Decreased fuel efficiency
- Rough idle or hesitation during acceleration
- Check engine light illuminated
Most Common Causes
- 1
Faulty ignition coil K
The ignition coil itself may have high internal resistance or an open circuit, preventing the PCM from properly controlling it and causing the control circuit voltage to remain high.
- 2
Wiring or connector issues
Corroded, loose, or damaged wiring and connectors between the PCM and ignition coil K can increase circuit resistance and prevent proper voltage control.
- 3
PCM driver circuit failure
The power control module's internal ignition coil driver transistor for coil K may be defective, limiting its ability to pull the control circuit to ground.
- 4
Spark plug or ignition timing issues
A fouled or incorrect spark plug for cylinder K or timing problems can cause the ignition system to work harder, triggering a high control circuit voltage fault.
How to Diagnose It
- 1
Check Faulty ignition coil K — The ignition coil itself may have high internal resistance or an open circuit, preventing the PCM from properly controlling it and causing the control circuit voltage to remain high.
- 2
Check Wiring or connector issues — Corroded, loose, or damaged wiring and connectors between the PCM and ignition coil K can increase circuit resistance and prevent proper voltage control.
- 3
Check PCM driver circuit failure — The power control module's internal ignition coil driver transistor for coil K may be defective, limiting its ability to pull the control circuit to ground.
- 4
Check Spark plug or ignition timing issues — A fouled or incorrect spark plug for cylinder K or timing problems can cause the ignition system to work harder, triggering a high control circuit voltage fault.
How to Fix It
- 1
Replace ignition coil K
Remove the faulty ignition coil from cylinder K and install a new OEM or quality replacement. Test the circuit voltage after installation to confirm the code clears.
- 2
Inspect and repair wiring and connectors
Check all wiring and connectors between the PCM and ignition coil K for corrosion, damage, or loose connections. Clean or replace connectors and repair damaged wires as needed.
- 3
Test and replace spark plug K
Remove and inspect the spark plug for cylinder K. If fouled or worn, replace it with the correct specification for your vehicle.
- 4
Have PCM diagnosed by professional
If coil, wiring, and spark plugs test normal, the PCM driver circuit may be faulty. Have a qualified technician perform in-depth PCM diagnostics or consider PCM replacement if internal failure is confirmed.
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