P1131

DTC P1131 - FRONT OXYGEN (A/F) SENSOR CIRCUIT MALFUNCTION (SHORT CIRCUIT)

DTC DETECTING CONDITION:
- Two consecutive driving cycles with fault

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

10BZ1: CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR.
1. Turn ignition switch to OFF.
2. Disconnect connector from ECM.

Connector & terminal (B136) No.7 - Chassis ground:

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

CHECK: Is the resistance more than 10 ohm?

YES: Go to step 10BZ2.

NO: Repair ground short circuit in harness between ECM and front oxygen (A/F) sensor connector.

10BZ2: CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR.

Connector & terminal (B136) No.20 - Chassis ground:

Measure resistance of harness between ECM connector and chassis ground.

CHECK: Is the resistance more than 10 ohm?

YES: Go to step 10BZ3.

NO: Repair ground short circuit in harness between ECM and front oxygen (A/F) sensor connector.

10BZ3: CHECK OUTPUT SIGNAL FOR ECM.
1. Connect connector to ECM.
2. Turn ignition switch to ON.

Connector & terminal (B136) No.7 (+) - Chassis ground (-):

3. Measure voltage between ECM connector and chassis ground.

CHECK: Is the voltage more than 4.5 Volt?

YES: Go to step 10BZ4.

NO: Go to step 10BZ5.

10BZ4: CHECK OUTPUT SIGNAL FOR ECM.

Connector & terminal (B136) No.7 (+) - Chassis ground (-):

Measure voltage between ECM connector and chassis ground.

CHECK: Is the voltage more than 10 Volt?

YES: Repair battery short circuit in harness between ECM and front oxygen (A/F) sensor connector. After repair, replace ECM.

NO: Repair poor contact in ECM connector.

10BZ5: CHECK OUTPUT SIGNAL FOR ECM.

Connector & terminal (B136) No.20 (+) - Chassis ground (-):

Measure voltage between ECM connector and chassis ground.

CHECK: Is the voltage more than 4.95 Volt?

YES: Go to step 10BZ6.

NO: Replace front oxygen (A/F) sensor.

10BZ6: CHECK OUTPUT SIGNAL FOR ECM.

Connector & terminal (B136) No.20 (+) - Chassis ground (-):

Measure voltage between ECM connector and chassis ground.

CHECK: Is the voltage more than 10 Volt?

YES: Repair battery short circuit in harness between ECM and front oxygen (A/F) sensor connector. After repair, replace ECM.

NO: Repair poor contact in ECM connector.