DTC P0325-11: Knock Sensor 1 Bank 1 or Single Sensor Circuit Short to Ground [11/2021 - ]: Description

WARNING: This page is about a different car, the 2025 Lexus NX 350, 2024 Lexus NX 350, 2023 Lexus NX 350, and 2022 Lexus NX 350. However, it is still accessible from the selected car via links, so may be relevant.

A flat-type knock control sensor (non-resonant type) has a structure that can detect vibrations between approximately 5 and 15 kHz.

The knock control sensor is fitted onto the engine block to detect engine knocking.

The knock control sensor contains a piezoelectric element which generates a voltage when it becomes deformed.

The voltage is generated when the engine block vibrates due to knocking. Any occurrence of engine knocking can be suppressed by delaying the ignition timing.

HINT:

When DTC P0325-11 is stored, the ECM enters fail-safe mode. During fail-safe mode, the ignition timing is delayed to its maximum retardation. Fail-safe mode continues until the ignition switch is turned off.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Note
P0325-11	Knock Sensor 1 Bank 1 or Single Sensor Circuit Short to Ground	The knock control sensor output voltage is less than 0.5 V for 1 second or more (1 trip detection logic).	Short in knock control sensor circuit Knock control sensor ECM	Comes on	SAE Code: P0327

Reference: Inspection using an oscilloscope

HINT:

The correct waveform is as shown.

ECM Terminal Name	Between KNK1 and EKNK
Tester Range	1 V/DIV., 1 ms./DIV.
Condition	Engine speed maintained at 4000 rpm after warming up engine