P0332: The knock sensor circuit on Bank 2 is reading too low
Knock Sensor 2 Circuit Low Input (Bank 2)
Yes, with care. The PCM will retard timing on Bank 2 as a safety measure. Avoid pushing the engine hard until the sensor is repaired. Do not use lower-octane fuel than recommended.
What it means
P0332 is a Bank 2 specific knock sensor fault that indicates the sensor circuit voltage is below the expected threshold. This only appears on V6, V8, or other multi-bank engines. The knock sensor generates a small AC voltage signal when it vibrates. If the circuit input reads consistently low, the most likely cause is a short to ground in the signal wire, a dead sensor, or a broken reference circuit. With no knock feedback from Bank 2, the PCM cannot protect those cylinders from detonation damage and trims timing conservatively.
Common causes
- Short to ground in the Bank 2 knock sensor signal wireDamaged insulation on the signal wire allows it to contact the block or a ground point, pulling the signal low.
- Failed Bank 2 knock sensorThe sensor piezoelectric element fails and outputs a low or zero voltage signal.
- Corroded or damaged sensor connector on Bank 2Pin corrosion causes high resistance, which the PCM interprets as a low-signal condition.
- Loose Bank 2 knock sensorTorque spec matters. A loose sensor does not make proper contact with the block and generates no signal.
What it costs
- Wiring or connector repair$80 to $250
- Knock sensor replacement (Bank 2)$150 to $400 installed
- Knock sensor under intake manifold$300 to $700 due to manifold removal labor
Symptoms
- Check engine light on, steady
- Reduced power and throttle response on Bank 2 cylinders
- Worse fuel economy
- Possible audible knock under hard acceleration if true detonation is occurring
What to do next
If P0325 is also set, both banks are affected and you should check the wiring harness for a common damage point. If P0332 is alone, focus on the Bank 2 sensor and its wiring. On many GM V6 and V8 engines, both knock sensors are located under the intake manifold. The repair cost is mostly labor. Inspect the harness for chafing near the block first before committing to manifold removal.
Lewis shows live Bank 2 timing retard values so you can see how aggressively the PCM is compensating for the missing knock signal. Download Lewis.
Related codes
FAQ
- Is P0332 the same as P0330?
- Similar but different. P0330 is a general circuit malfunction on Bank 2. P0332 specifically reports a low-voltage input, pointing toward a short to ground or a dead sensor.
- Can I damage the engine by ignoring P0332?
- Yes, over time. Without knock detection on Bank 2, actual detonation goes undetected. Sustained detonation damages pistons, rings, and bearings.
- Does P0332 affect all cylinders or just Bank 2?
- Just the Bank 2 cylinders. Bank 1 knock detection is handled by a separate sensor and circuit.