P2347
Cylinder 12 Above Knock/Combustion Vibration Sensor Threshold
The knock or combustion-vibration sensor monitors the structure-borne noise of each cylinder. The signal level for cylinder 12 has stayed above the diagnostic threshold for an extended period, indicating either persistent knock or an electrical fault that biases the channel high.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Persistent knocking on cylinder 12Common
- Sensor or wiring biased highPossible
- Gateway module routing CAN messages incorrectlyLess likely
Parts involved
- Knock Sensor
- Knock Sensor Wiring
- Cylinder 12 Combustion
P2347 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.