Knock Sensor 1 Circuit Low Input (Bank 1)
The knock sensor signal voltage is below the expected range. Usually points to a piezoelectric sensor that has lost its output, or a short to ground in the signal line.
Affected components
- Knock sensor
- Knock sensor wiring
Common causes
- High likelihood: Knock sensor failed
- Medium likelihood: Signal wire shorted to ground
- Low likelihood: Connector pins corroded - high contact resistance
Possible symptoms
- Check engine light on
- Power loss from defensive spark retard
- Increased fuel consumption
- Possible audible pinging under load
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- A drive cycle may be required after repair
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.