Damaged or chafed knock sensor power wire shorting to ground or to another circuit; Corroded, loose, or water-intruded knock sensor connector pins; Failed knock sensor with an internally shorted power circuit; Open or high-resistance ground connection at the sensor or engine block; Faulty ECM power supply driver for the knock sensor circuit, though this is less common; Harness damage from rodents, heat, or previous engine work near the knock sensor

DTC codes / Nissan codes / P1324

P1324 · NissanKnock Sensor Power Source Circuit Low Voltage

Q: What does code P1324 mean?

Knock Sensor Power Source Circuit Low Voltage. P1324 on Nissan vehicles means the engine control module (ECM) has detected that the power supply circuit feeding the knock sensor is at a lower voltage than expected, so the sensor cannot generate a reliable knock signal. The ECM monitors this circuit and sets the code when the voltage on the sensor's power feed drops below its calibrated threshold, which can happen because of a wiring fault, a poor connection, or a failing sensor.

P1324 on Nissan vehicles means the engine control module (ECM) has detected that the power supply circuit feeding the knock sensor is at a lower voltage than expected, so the sensor cannot generate a reliable knock signal. The ECM monitors this circuit and sets the code when the voltage on the sensor's power feed drops below its calibrated threshold, which can happen because of a wiring fault, a poor connection, or a failing sensor.

SystemPowertrain

Code typeNissan specific

SeverityMedium

Fix difficultyIntermediate

AreaIgnition system and misfire

Symptoms you may notice

Illuminated check engine light, often with no other symptoms besides the warning light
Reduced engine performance or sluggish acceleration as the ECM retards ignition timing to protect the engine
Lower fuel economy than normal because the ECM defaults to a conservative timing strategy
Occasional rough idle or hesitation under light throttle
In some cases a stored pending code without the light staying on, especially after a cold start

Common causes, most likely first

Damaged or chafed knock sensor power wire shorting to ground or to another circuit
Corroded, loose, or water-intruded knock sensor connector pins
Failed knock sensor with an internally shorted power circuit
Open or high-resistance ground connection at the sensor or engine block
Faulty ECM power supply driver for the knock sensor circuit, though this is less common
Harness damage from rodents, heat, or previous engine work near the knock sensor

How to diagnose and fix it

Scan all modules and record freeze-frame data to confirm P1324 is active and not a ghost code from a low battery
Inspect the knock sensor connector and harness for corrosion, chafing, or loose pins, repairing as needed
Measure voltage on the knock sensor power feed with the key on and compare to the Nissan service specification
Check the sensor ground circuit for excessive resistance using a voltage drop test
Test the knock sensor itself with a multimeter for internal shorts or opens, replacing it if out of specification
If wiring and sensor test good, check the ECM connector pins and perform a continuity test back to the ECM
Clear the code and perform a road test with live data to verify the knock sensor signal returns and the code does not reset

Why knock sensor power codes mislead

A weak or failing battery or a poor engine ground can drag the knock sensor supply voltage low and set P1324 even when the sensor and its wiring are healthy.
Technicians often replace the knock sensor first, but on many Nissans the real fault is a corroded connector pin or a harness rubbed through near the intake manifold.
P1324 does not always mean the sensor has failed; the ECM may set it from a momentary voltage dip during cranking if the battery is marginal.
After engine replacement or major intake work, a pinched or unclipped knock sensor harness is a frequent cause that visual inspection alone can miss.
The knock sensor circuit shares ground paths with other engine sensors, so a bad ground can set P1324 alongside codes for other sensors without any of them being faulty.

Can I keep driving with P1324?

You can usually drive the vehicle short distances to a repair shop, but avoid heavy throttle and towing because the ECM may not be able to retard timing properly, which risks engine damage. If the check engine light flashes or the engine runs poorly, stop driving and have it diagnosed promptly.

Tools that help

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Guidance is general and written for Nissan vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.