OBD-II code · Powertrain (generic)

P0332 Knock Sensor 2 Circuit Low Input (Bank 2)

Knock sensor 2 (bank 2) reports a signal level below the diagnostic threshold. The sensor is a piezo element bolted to the engine block; output should be a small AC voltage on each combustion event. A cold or open sensor reads 0 V; a loose mounting bolt damps the signal. Without knock detection, the ECM retards spark globally as a safety measure — fuel economy and power suffer.

Is it safe to drive with P0332?

Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.

Common causes

  • Most likelyKnock sensor failed
  • PossibleSignal wire shorted to ground
  • Less likelyConnector pins corroded - high contact resistance

Symptoms

  • Check engine light on
  • Power loss from defensive spark retard
  • Increased fuel consumption
  • Possible audible pinging under load

Repair at a glance

Difficulty
Hard
DIY friendly
Best left to a mechanic
Typical labour
1–6 h
Emissions test
Likely to fail
After the fix
A drive cycle is needed before the light stays off
Parts involved
Knock Sensor, Sensor Wiring

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.