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P1325

DTC P1325 - KNOCK SENSOR CIRCUIT LOW 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

11CE1: 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 11CE3.

NO: Go to step 11CE2.

11CE2: CHECK HARNESS BETWEEN 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 11CE5.

NO: Go to step 11CE6.

11CE3: 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 11CE4.

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).

11CE4: 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.

11CE5: 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.

11CE6: 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.