HomeTrouble CodesP2335

P2335 — Ignition Coil L Secondary Circuit

Manufacturer-specificPowertrain (engine & transmission)

P2335 indicates that the engine control module has detected a fault in the secondary (high‑voltage) circuit of ignition coil L. The secondary circuit includes the coil’s internal winding, the spark plug wire, and the spark plug itself. A problem here prevents the coil from delivering sufficient voltage to fire the cylinder.

Symptoms

What causes it — most likely first

1. Failed ignition coil L

The coil’s secondary winding can open or short, preventing proper high‑voltage generation.

2. Damaged or corroded coil connector/wiring

Broken wires, loose terminals, or corrosion interrupt the secondary circuit path.

3. Faulty spark plug or plug wire for cylinder L

A fouled, cracked, or incorrectly gapped plug can cause an open secondary circuit.

4. Defective ignition control module (if separate)

The module that drives coil L may not supply the required trigger signal.

5. Engine control module (PCM/ECM) fault

Rare; only considered after all coil, wiring, and module checks are normal.

How it's diagnosed

  1. Retrieve the code and freeze‑frame data; note any related misfire codes.
  2. Visually inspect coil L connector, harness, and plug wire for damage, corrosion, or loose connections.
  3. Measure secondary resistance of coil L per manufacturer specifications; compare with a known good coil.
  4. Swap coil L with a coil from another cylinder; if the code follows the coil, the coil is defective.
  5. Inspect and test the spark plug and plug wire for cylinder L; replace if worn or damaged.
  6. If the above are normal, test the ignition control module output signal to coil L.
  7. Only after all other components verify good, evaluate PCM/ECM for internal driver failure.

Code facts & related codes

SystemPowertrain (engine & transmission)
StandardizationManufacturer-specific (P1/B1/C1/U1)

Frequently asked

Does P2335 mean the PCM is bad?

Very rarely. The code almost always points to the coil, its wiring, or the spark plug. The PCM is only implicated after all other possibilities are ruled out.

Can a bad spark plug cause this code?

Yes. A fouled, cracked, or incorrectly gapped plug can create an open secondary circuit that triggers P2335.

Is it safe to continue driving with this code?

Driving with a persistent misfire can damage the catalytic converter and increase emissions; repair should be performed promptly.

Should I replace the ignition coil immediately?

Diagnose first. Swapping the suspect coil with a known good one confirms whether the coil itself is the cause before replacement.