Ignition Coil Secondary Circuit Malfunction
The P2302 code indicates a problem in the secondary circuit of ignition coil 'A'. This circuit includes the coil itself, the spark plug wire, and the spark plug. The Powertrain Control Module (PCM) detects an abnormal voltage or current in the secondary ignition circuit, often due to excessive resistance or a short. This can lead to misfires, reduced engine performance, and increased emissions.
01. Most Common Causes
- Faulty ignition coil
- Worn or damaged spark plugs
- Open or shorted spark plug wire
- Carbon tracking on spark plug or coil boot
02. Symptoms You Will Notice
- Engine misfire
- Check Engine Light illuminated
- Rough idle
- Decreased fuel economy
03. Step-by-Step Diagnosis
Step 1: Scan for codes and note freeze frame data.
Step 2: Inspect ignition coil, spark plug wires, and spark plugs for visible damage.
Step 3: Swap the suspect coil with another cylinder and see if the code follows.
Step 4: Test coil primary and secondary resistance with a multimeter.
Step 5: Check for spark at the spark plug using a spark tester.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can cause catalytic converter damage due to unburned fuel. Short trips to a repair shop are okay.
How much does it cost to fix?▼
Typically $50-$150 for a single coil replacement, plus labor if done by a shop. Spark plugs and wires may add to the cost.