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P0325

DTC P0325 - KNOCK SENSOR CIRCUIT HIGH INPUT

DTC DETECTING CONDITION:
- Immediately at fault recognition

TROUBLE SYMPTOM:
- Poor driving performance
- knocking occurs.

CAUTION: After repair or replacement of faulty parts, conduct CLEAR MEMORY MODE and INSPECTION MODE. Refer to How To Clear Diagnostic trouble codes.




WIRING DIAGRAM

11AA1: CHECK HARNESS BETWEEN KNOCK SENSOR AND ECM CONNECTOR.
1. Turn ignition switch to OFF.
2. Disconnect connector from ECM.

Connector & terminal (B136) No.4 - Chassis ground:




3. Measure resistance between ECM harness connector and chassis ground.

CHECK: Is the resistance more than 700 K.Ohm?

YES: Go to step 11AA3.

NO: Go to step 11AA2.

11AA2: CHECK HARNESS BETWEEN KNOCK SENSOR AND ECM CONNECTOR.

Connector & terminal (B136) No.4 - Chassis ground:




Measure resistance of harness between ECM connector and chassis ground.

CHECK: Is the resistance less than 400 K.Ohm?

YES: Go to step 11AA5.

NO: Go to step 11AA6.

11AA3: CHECK KNOCK SENSOR.
1. Disconnect connector from knock sensor.

Terminal No.2 - Engine ground:




2. Measure resistance between knock sensor connector terminal and engine ground.

CHECK: Is the resistance more than 700 K.Ohm?

YES: Go to step 11AA4.

NO: Repair harness and connector.

NOTE: In this case, repair the following:
- Open circuit in harness between knock sensor and ECM connector
- Poor contact in knock sensor connector
- Poor contact in coupling connector (B21)

11AA4: CHECK CONDITION OF KNOCK SENSOR INSTALLATION.

CHECK: Is the knock sensor installation bolt tightened securely?

YES: Replace knock sensor.

NO: Tighten knock sensor installation bolt securely.

11AA5: CHECK KNOCK SENSOR.
1. Disconnect connector from knock sensor.

Terminal No.2 - Engine ground:




2. Measure resistance between knock sensor connector terminal and engine ground.

CHECK: Is the resistance less than 400 K.Ohm?

YES: Replace knock sensor.

NO: Repair ground short circuit in harness between knock sensor connector and ECM connector.

NOTE: The harness between both connectors is shielded.
Repair short circuit of harness together with shield.

11AA6: CHECK INPUT SIGNAL FOR ECM.
1. Connect connectors to ECM and knock sensor.
2. Turn ignition switch to ON.

Connector & terminal (B136) No.4 (+) - Chassis ground (-):




3. Measure voltage between ECM and chassis ground.

CHECK: IS the voltage more than 2 Volt?

YES: Even if MIL lights up, the circuit has returned to a normal condition at this time. (However, the possibility of poor contact still remains.)

NOTE: In this case, repair the following:
- Poor contact in knock sensor connector
- Poor contact in ECM connector
- Poor contact in coupling connector (B21)

NO: Repair poor contact in ECM connector.