How to Fix P1332 Error

If your check engine light is on and a scan tool shows P1332, you’re dealing with a specific issue: the engine control module has detected an abnormal voltage reading from the knock sensor 2 circuit. That’s not just a warning it means the car may be limiting power, running rough, or refusing to accelerate normally. Fixing P1332 isn’t about clearing the code and hoping for the best. It’s about diagnosing what’s actually wrong with the sensor, its wiring, or how the ECU interprets the signal.

What does P1332 actually mean?

P1332 stands for “Knock Sensor 2 Circuit Low Input.” It’s a generic OBD-II trouble code that applies to many vehicles especially Nissan, Infiniti, and some Mitsubishi models but the exact location and behavior of knock sensor 2 varies by year and engine. Unlike generic codes like P0300, P1332 points directly to the sensor’s electrical output being lower than expected not necessarily that the sensor is broken, but that the signal falls outside acceptable thresholds. You’ll find more context in our detailed breakdown of the P1332 code definition.

When should you act on P1332?

You should investigate right away if you see P1332 along with symptoms like hesitation under acceleration, reduced power, or knocking/pinging sounds especially when climbing hills or towing. Some drivers ignore it because the car still runs, but over time, unaddressed knock sensor issues can cause the ECU to pull timing excessively, leading to poor fuel economy or even long-term engine stress. If the code appears without symptoms, it’s still worth checking intermittent wiring faults often start quietly.

How to fix P1332 step by step

Start with the simplest checks first:

Inspect the knock sensor 2 connector (usually near the intake manifold or cylinder head) for corrosion, bent pins, or loose fit.
Check the wiring harness between the sensor and ECU for chafing, heat damage, or pinching especially near exhaust components.
Test sensor resistance with a multimeter: most knock sensors read between 500–600 kΩ at room temperature. A reading far outside that range suggests internal failure.
Verify reference voltage at the sensor connector: with the key on (engine off), you should see ~5V on the signal wire. No voltage means a break in the supply line or ECU issue.

If those pass, consider whether the sensor was replaced with a non-OEM part the aftermarket knock sensors for many Nissan VQ engines have inconsistent output and trigger P1332 even when wired correctly. Genuine OEM or high-reliability replacements are worth the extra cost here.

Common mistakes people make fixing P1332

Replacing the knock sensor without checking wiring is the most frequent error. Many assume “sensor = problem,” but damaged insulation or a broken ground wire causes more P1332 cases than faulty sensors. Another mistake is clearing the code before verifying repairs some shops reset it and call it done, but the code will return within a few drive cycles if the root cause remains. Also, don’t skip checking for related codes like P0325 or P0327; they often appear alongside P1332 and point to broader knock sensor system issues.

Where is knock sensor 2 located?

It depends on the engine. On a Nissan Altima with a 2.5L QR25DE, knock sensor 2 sits on the rear of the cylinder block, near the oil filter housing. In a 3.5L VQ35DE, it’s mounted on the intake manifold underside harder to reach without removing parts. Always confirm the location using a factory service manual or verified repair database like ALLDATA. Guessing leads to wasted time and missed diagnostics.

What else could cause P1332 besides the sensor?

A failing engine control unit rarely causes P1332, but it’s possible and usually only considered after ruling out wiring, connectors, and the sensor itself. More commonly, water intrusion into the connector (from washing or rain), oil contamination on the sensor mounting surface, or even excessive carbon buildup altering engine harmonics can skew readings. You’ll see these scenarios covered in our full P1332 diagnostic trouble code guide.

Next steps after confirming the fix

After replacing the sensor or repairing wiring, clear the code and take the car for a test drive that includes steady highway cruising and moderate acceleration enough to generate engine load but not full throttle. Monitor live data for knock sensor 2 voltage: it should fluctuate smoothly between ~0.1V and ~4.8V under load. If the code returns, recheck grounds and verify no other fault codes are active. For model-specific details, refer to the vehicle-specific P1332 troubleshooting page.

Quick checklist before you begin: