Ignition Coil L Primary/Secondary Circuit Malfunction
P0362 indicates a malfunction in the ignition coil L (driver side) primary or secondary circuit, meaning the PCM cannot properly control or detect the coil's operation. This prevents the spark plug from firing correctly on that cylinder, causing misfires and rough running.
What You Might Notice
- Check Engine Light (MIL) illumination
- Engine misfire on cylinder L (rough idle or acceleration)
- Reduced fuel economy
- Loss of engine power
- Intermittent rough running
Most Common Causes
- 1
Bad Coil-on-Plug (COP) Ignition Coil
The ignition coil itself has failed electrically, preventing it from generating spark. This is the most common cause of P0362.
- 2
Loose or Corroded Coil Connector
Poor electrical connection at the coil connector due to loose pins, corrosion, or broken connector locks interrupts the signal between PCM and coil.
- 3
Short or Open in COP Driver Circuit Wiring
The wiring harness controlling the coil has a short to voltage/ground or an open circuit break, preventing proper signal transmission from the PCM.
- 4
Faulty Powertrain Control Module (PCM)
The PCM's ignition coil driver circuit is defective, unable to send the correct control signal to the coil despite the coil itself being functional.
How to Diagnose It
- 1
Check Bad Coil-on-Plug (COP) Ignition Coil — The ignition coil itself has failed electrically, preventing it from generating spark. This is the most common cause of P0362.
- 2
Check Loose or Corroded Coil Connector — Poor electrical connection at the coil connector due to loose pins, corrosion, or broken connector locks interrupts the signal between PCM and coil.
- 3
Check Short or Open in COP Driver Circuit Wiring — The wiring harness controlling the coil has a short to voltage/ground or an open circuit break, preventing proper signal transmission from the PCM.
- 4
Check Faulty Powertrain Control Module (PCM) — The PCM's ignition coil driver circuit is defective, unable to send the correct control signal to the coil despite the coil itself being functional.
How to Fix It
- 1
Replace the Ignition Coil
Remove the failed coil-on-plug from cylinder L by disconnecting the connector and unbolting it from the spark plug well. Install a new OEM or quality aftermarket coil and reconnect, then clear the code.
- 2
Inspect and Repair Coil Connector
Check the connector at the ignition coil for loose pins, corrosion, or damage. Clean with electrical contact cleaner, ensure connector locks are engaged, and reseat firmly. Replace the connector if pins are damaged.
- 3
Check and Repair Wiring Harness
Inspect the wiring harness between PCM and ignition coil L for cuts, pinches, or corrosion. Use a multimeter to test for continuity and shorts. Repair or replace damaged sections of wiring as needed.
- 4
Replace PCM if Necessary
If coil, connector, and wiring all test good, the PCM driver circuit has failed. This requires PCM replacement and reprogramming, which should be performed by a dealer or specialist.
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