Fault-Code Library · Knock control
P0325: Knock sensor circuit malfunction
The ECU is not receiving a plausible signal from the knock sensor circuit.
Common symptoms
- •Reduced power
- •Poor acceleration
- •Engine warning light
- •Possible pinging under load
Likely causes
- •Failed knock sensor
- •Damaged wiring
- •Incorrect torque or mounting issue
- •Engine noise or poor fuel quality confusing knock control
First checks
- •Inspect sensor wiring and connector
- •Check for engine mechanical noise
- •Verify fuel quality and sensor mounting before replacement
Important
Knock-control faults can make the ECU reduce power to protect the engine.
A fault code identifies a detected condition, not a failed part. Confirm manufacturer-specific subcodes and live data.
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