OBD-II Code P0332 — What It Means & How to Fix It

What Does This Error Mean?

P0332 means the knock sensor circuit on Bank 2 is reading a voltage that is too low. Bank 2 is the side of the engine that does NOT have cylinder 1. The knock sensor is supposed to generate a small voltage signal when it detects vibrations — but the ECM is seeing a signal that's weaker than it should be. This is the low-voltage counterpart to P0333 (circuit high). The engine will run, but the ECM can't properly detect knock on that bank.

Affected Models

V6 and V8 vehicles 1996+
Common in Toyota Tacoma and 4Runner V6
Common in Chevrolet and GMC V8 trucks
Common in Nissan Pathfinder and Frontier V6
Common in Honda Accord and Pilot V6

Common Causes

Knock sensor failure — the sensor's piezoelectric element is producing a weak or no signal
Short to ground in the knock sensor signal wire causing the voltage to drop too low
Corroded connector or poor connection at the Bank 2 knock sensor
Wiring damage that has reduced the signal before it reaches the ECM
ECM reference voltage issue — not providing the correct bias voltage to the knock sensor circuit

How to Fix It

Scan for all codes and check if you also have P0330 (Bank 2 knock sensor circuit malfunction) or P0333 (circuit high). The combination of codes tells you whether this is a simple low-signal issue or a more complex circuit problem.

A low signal alongside a random misfire code could mean the ECM is defaulting to conservative timing, which sometimes causes slight rough running.
Locate the Bank 2 knock sensor. It is typically threaded into the engine block under the intake manifold. Inspect the mounting and wiring connector for obvious damage, oil fouling, or corrosion. Clean the connector terminals with electrical contact cleaner.

Bank 2 is harder to access on transverse-mounted V6 engines — the sensor often faces the firewall.
Check for a short to ground in the signal wire. Unplug the knock sensor connector and use a multimeter to test resistance between the signal wire and a chassis ground. It should read very high resistance (open circuit). A low reading indicates a shorted wire.

A short to ground drags the signal voltage down and is a common cause of P0332.
Test the knock sensor resistance according to your service manual. Unplug the sensor and probe across its terminals. An out-of-spec resistance reading or an open circuit (OL) indicates a failed sensor that needs replacement.

Knock sensor resistance specs vary widely — always verify for your specific vehicle.
If the sensor and wiring both test correctly, have a mechanic verify the ECM reference voltage on the knock sensor circuit. The ECM provides a small bias voltage that the sensor modulates. If this reference voltage is missing or too low, the ECM itself may have a problem.

ECM issues are rare — fully rule out the sensor and wiring first.

When to Call a Professional

If the knock sensor connector is clean and the wiring appears intact, a mechanic should verify whether the sensor is generating any signal at all. Some knock sensors can only be properly tested with an oscilloscope while the engine is running. Don't replace the ECM without first thoroughly ruling out the sensor and wiring. Expect $150-$400 for knock sensor replacement, depending on how accessible Bank 2 is on your engine.

Frequently Asked Questions

Is P0332 dangerous to ignore?

Not immediately dangerous, but it's not something to ignore long-term. With the Bank 2 knock sensor reading low, the ECM may not detect engine knock on that bank. If your engine starts knocking — from low-octane fuel, a lean condition, or carbon buildup — the ECM won't reduce timing appropriately. Unchecked knock can damage pistons and engine bearings over time. Fix it within a few weeks.

Can I use higher octane fuel to help while I wait to fix P0332?

Using higher octane fuel will reduce the likelihood of knock occurring. This gives the ECM less to worry about on Bank 2 while the sensor is unreliable. However, it is not a permanent fix — it just reduces the risk of knock damage while you arrange the repair. Don't use premium fuel as a substitute for fixing the sensor.

How long does knock sensor replacement take?

If the knock sensor is easily accessible, it's a 30-60 minute job. On engines where the sensor is buried under the intake manifold, the total time can be 2-4 hours including manifold removal and reinstallation. V6 engines in front-wheel-drive vehicles typically require the most labor due to tight packaging.