Ignition Coil B Primary/Secondary Circuit Malfunction

The computer is not getting the right signal from the ignition coil that fires cylinder 2, meaning that cylinder might not spark properly, leading to misfires.

The powertrain control module (PCM) monitors the ignition coil circuit. If it detects an open circuit, short to ground, or incorrect voltage (usually below 0.5V or above 5.0V), it triggers this code.

Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.

1. 11. Check engine oil and coolant levels; top off if needed. Decision: Proceed if normal, skip if low or contaminated.
2. 22. Inspect wiring and connectors at ignition coil B for damage or corrosion. Decision: Repair or replace as needed before further tests.
3. 33. Measure voltage at the ignition coil connector with ignition on (engine off). You should see about 12V. Decision: If not, check wiring back to the PCM.
4. 44. Check the signal wire from the PCM to the ignition coil with a scope or multimeter; it should oscillate between 0V and 5V when cranking. Decision: If no signal, suspect PCM failure.
5. 55. Swap the ignition coil with another cylinder (if applicable). Clear codes and run engine. Decision: If code changes to the other cylinder, replace the ignition coil.

• Faulty ignition coil for cylinder 2
• Damaged wiring or connectors to the ignition coil
• Faulty ECM/PCM
• Bad spark plug or excessive wear
• Oil or fluid contamination on the ignition coil

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