A/T

DTC P1133 - FRONT OXYGEN (A/F) SENSOR HEATER CIRCUIT HIGH INPUT

DTC DETECTING CONDITION:
- Two consecutive driving cycles with fault

CAUTION: After repair or replacement of faulty parts, conduct CLEAR MEMORY MODE and INSPECTION MODE.

Wiring Diagram:

WIRING DIAGRAM

11BZ1: CHECK OUTPUT SIGNAL FROM ECM.

1. Turn ignition switch to ON.

Connector & Terminal - [(B134) No.23 (+) - Chassis Ground (-)]:

2. Measure voltage between ECM connector and chassis ground.

CHECK: Is the voltage more than 8 V?

YES: Go to step 11BZ3.

NO: Go to step 11BZ2.

11BZ2: CHECK OUTPUT SIGNAL FROM ECM.

Connector & Terminal - [(B134) No.22 (+) - Chassis Ground (-)]:

Measure voltage between ECM connector and chassis ground.

CHECK: Is the voltage more than 8 V?

YES: Go to step 11BZ3.

NO: Go to step 11BZ4.

11BZ3: CHECK FRONT OXYGEN (AIF) SENSOR HEATER CURRENT.

1. Turn ignition switch to OFF.
2. Repair battery short circuit in harness between ECM and front oxygen (A/F) sensor connector.
3. Turn ignition switch to ON.
4. Read data of front oxygen (A/F) sensor heater current using Subaru Select Monitor or the OBD-II general scan tool.

NOTE:
- Subaru Select Monitor
For detailed operation procedure, refer to the "READ CURRENT DATA SHOWN ON DISPLAY FOR ENGINE". Refer to Normal Scan Data values
- OBD-II general scan tool
For detailed operation procedure, refer to the OBD-II General Scan Tool Instruction Manual.

CHECK: Is the value more than 2.3 A?

YES: Replace ECM.

NO: END

11BZ4: CHECK OUTPUT SIGNAL FROM ECM.

Connector & Terminal - [(B134) No.23 (+) - Chassis Ground (-)]:

Measure voltage between ECM connector and chassis ground.

CHECK: Does the voltage change more than 8 V by shaking harness and connector of ECM while monitoring the value with voltage meter?

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

NO: Go to step 11BZ5.

11BZ5: CHECK OUTPUT SIGNAL FROM ECM.

Connector & Terminal - [(B134) No.22 (+) - Chassis Ground (-)]:

Measure voltage between ECM connector and chassis ground.

CHECK: Does the voltage change more than8 V by shaking harness and connector of ECM while monitoring the value with voltage meter?

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

NO: END