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P1325

CD: 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. Clearing Diagnostic Trouble Codes





WIRING DIAGRAM

10CD1: 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 mare than 700 Kohm?

YES: Go to step 10CD3.

NO: Go to step 10CD2.

10CD2: 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 Kohm

YES: Go to step 10CD5.

NO: Go to step 10CD6.

10CE3: 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 Kohm?

YES: Go to step 10CD4.

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)

10CE4: 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.

10CE5: 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 Kohm?

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.

10CE6: 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 V?

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.