P2309
PowertrainIgnition Systemmoderate severityIgnition Coil B Primary Control Circuit/Open
What P2309 Means
The PCM detects an open or fault in the primary control circuit for ignition coil B. This can cause misfires and poor engine performance.
Symptoms
- Engine misfire
- Check engine light on
- Rough idle or loss of power
Common Causes
- Faulty ignition coil B
- Open in coil primary wiring
- Corroded coil connector
- PCM driver circuit fault
Diagnostic Steps
- Scan for coil and misfire codes
- Inspect coil B connector and wiring
- Test coil primary circuit continuity
- Replace ignition coil if faulty
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