P0332 fault code: Knock Sensor 2 Circuit Low

P0332 means “Knock Sensor 2 Circuit Low” — an ignition system and misfire fault in the powertrain.

Can I DIY?

Professional-only boundary. No licensed DIY path for this code. Book a garage and do not drive until it is checked.

Do not DIYReviewed page boundary
ToolsSpecialist equipment

This is the conservative boundary from the reviewed code record. This page has no frozen site-wide safety grade, so it does not publish a repair route.

What to tell the garage about P0332

Stop driving now. Knock sensor 2 is reporting a circuit voltage that is too low. That sensor helps the computer detect harmful knock and protect the engine. This page has no verified driving grade, so do not assume it is safe to keep driving.

Take these reviewed, code-specific details with you. They help the garage confirm the fault without turning this page into a repair procedure.

  • Knock Sensor 2 Circuit Low: Registration number
  • Knock Sensor 2 Circuit Low: Exact code P0332 and any other codes from the same scan
  • Knock Sensor 2 Circuit Low: Whether the engine management light is steady or flashing
  • Knock Sensor 2 Circuit Low: Any knock, ping, or loss of power you noticed
P03xxIgnition system and misfire
MOT fail riskif the warning light stays on

What does P0332 mean?

P0332 is a generic (SAE standard) powertrain code reported by your car’s engine control unit. It sits in the P03xx block, which covers ignition system and misfire. The stored description is “Knock Sensor 2 Circuit Low”. The code itself tells you which circuit or system tripped the fault — not always the exact part that failed.

Will P0332 fail an MOT?

An illuminated engine management light is a Major defect at MOT (automatic fail) until the fault is repaired and the light stays off. P0332 is a knock-sensor circuit flag, not an MOT emissions reading.

Before booking your test, check what usually fails on your car: see our MOT pass rates by make and model, built from 33.1 million DVSA tests.

Related guides

Car diagnostic test cost: compare the scopeUK booking marketplaces currently publish diagnostic averages of about £52–£65. Engine management light on: steady or flashing?A steady engine management light means the computer has stored a fault. Drive with caution and get the code read. A flashing light is different — stop when it is safe. Flashing engine management light and juddering: stop and recoverNo — do not continue the journey. A flashing engine management light with the car juddering is a stop-driving situation: ease off only enough to reach the nearest place of relat…
P0300Random/Multiple Cylinder Misfire Detected P0301Cylinder 1 Misfire Detected P0302Cylinder 2 Misfire Detected P0303Cylinder 3 Misfire Detected P0304Cylinder 4 Misfire Detected P0305Cylinder 5 Misfire Detected P0306Cylinder 6 Misfire Detected P0307Cylinder 7 Misfire Detected

P0332 — quick answers

Is it safe to drive with P0332?

Stop driving now. Driveability guidance is not available for this code — treat as do not drive until checked. A low knock-sensor-2 circuit reading is ungraded here, so recovery is the safe default.

Will P0332 fail my MOT?

An illuminated engine management light is a Major defect at MOT (automatic fail) until the fault is repaired and the light stays off. P0332 is a knock-sensor circuit flag, not an MOT emissions reading.

Fault-code identifiers are standard diagnostic facts. Their explanations and diagnostic guidance on this site are original editorial summaries, not reproduced SAE wording. MOT defect rules reflect the DVSA MOT inspection manual (2026). This page is general guidance for UK drivers, not a substitute for a professional diagnosis.