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P0356OBD-IIENGINEHigh if CEL flashing.

Ignition Coil F Primary/Secondary Circuit Malfunction

Common Symptoms

  • Check engine light on
  • Cylinder 6 misfire
  • Rough idle

Most Likely Root Causes

  • Faulty coil cylinder 6
  • Wiring open/short
  • PCM driver failure

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Severity / Derate Risk

High if CEL flashing.

Component Location

Coil F = cylinder 6.

Manufacturer Notes

Same as P0351 for cylinder 6.

Also diagnosing J1939 SPN/FMI codes?

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