P1132
DTC P1132 - FRONT OXYGEN (A/F) SENSOR HEATER CIRCUIT LOW INPUTDTC 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
10CA1: CHECK ANY OTHER DTC ON DISPLAY
CHECK: Does the Subaru Select Monitor or OBD-II general scan tool indicate DTC P1132 and P0141 at the same time?
YES: Go to step 10CA2.
NO: Go to step 10CA5.
10CA2: CHECK GROUND CIRCUIT OF ECM.
Connector & terminal (B134) No.35 - Chassis ground:
Measure resistance of harness between ECM connector and chassis ground.
CHECK: Is the resistance less than 5 ohm?
YES: Go to step 10CA6.
NO: Repair harness and connector.
NOTE: In this case, repair the following:
- Open circuit in harness between ECM and engine ground terminal
- Poor contact in ECM connector
Poor contact in coupling connector (B22)
10CA3: CHECK GROUND CIRCUIT OF ECM.
1. Repair harness and connector.
NOTE: In this case, repair the following:
- Open circuit in harness between ECM and engine ground terminal
- Poor contact in ECM connector
- Poor contact in coupling connector (B22)
Connector & terminal (B134) No.34 - Chassis ground:
2. Measure resistance of harness between ECM connector and chassis ground.
CHECK: Is there resistance less than 5 ohm?
YES: Go to step 10CA6.
NO: Repair harness and connector.
NOTE: In this case, repair the following:
- Open circuit in harness between ECM and engine ground terminal
- Poor contact in ECM connector Poor contact in coupling connector (B22)
10CA4: CHECK POWER SUPPLY CIRCUIT OF ECM.
1. Disconnect connectors from ECM.
2. Turn ignition switch to ON.
Connector & terminal (B136) No.3 (+) - (B134) No.34 (-):
3. Measure power supply voltage between ECM connector terminals.
CHECK: Is the voltage more than 8 Volt?
YES: Go to step 10CA3.
NO: Repair open or ground short circuit in harness of power supply circuit.
10CA5: CHECK POWER SUPPLY CIRCUIT OF ECM.
Connector & terminal (B136) No.3 (+) - (B136) No.35 (-):
Measure power supply voltage between ECM connector terminals.
CHECK: Is the voltage more than 8 Volt?
YES: Go to step 10CA4.
NO: Repair open or ground short circuit in harness of power supply circuit.
10CA6: CHECK CURRENT DATA.
1. Start engine
2. Read data of front oxygen (A/F) sensor heater current using Subaru Select Monitor or 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 scan tool
For detailed operation procedures, refer to the OBD-II General Scan Tool Instruction Manual.
CHECK: Is the value more than 0.2 A?
YES: Repair poor contact in connector.
NOTE: In this case, repair the following:
- Poor contact in front oxygen (A/F) sensor connector
- Poor contact in ECM connector
NO: Go to step 10CA7.
10CA7: CHECK OUTPUT SIGNAL FROM ECM.
1. Start and idle the engine.
Connector & terminal (B134) No.22 (+) - Chassis ground (-):
2. Measure voltage between ECM connector and chassis ground.
CHECK: Is the voltage less than 1.0 Volt?
YES: Go to step 10CA9.
NO: Go to step 10CA8.
10CA8: 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 less than 1.0 Volt by shaking harness and connector of ECM while monitoring the value with voltage meter?
YES: Repair poor contact in ECM connector.
NO: Go to step 10CA9.
10CA9: CHECK OUTPUT SIGNAL FROM ECM.
Connector & terminal (B134) No.23 (+) - Chassis ground (-):
Measure voltage between ECM connector and chassis ground.
CHECK: Is the voltage less than 1.0 Volt?
YES: Go to step 10CA11.
NO: Go to step 10CA10.
10CA10: 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 less than 1.0 Volt by shaking harness and connector of ECM while monitoring the value with voltage meter?
YES: Repair poor contact in ECM connector.
NO: Go to step 10CA11.
10CA11: CHECK POWER SUPPLY TO FRONT OXYGEN (A/F) SENSOR.
1. Turn ignition switch to OFF.
2. Disconnect connector from front oxygen (A/F) sensor.
3. Turn ignition switch to ON.
Connector & terminal (E24) No 2 (+) - Engine ground (-):
4. Measure voltage between front oxygen (A/F) sensor connector and engine ground.
CHECK: Is the voltage more than 10 Volt?
YES: Go to step 10CA12.
NO: Repair power supply line.
NOTE: In this case, repair the following:
- Open circuit in harness between main relay and front oxygen (A/F) sensor connector
- Poor contact in front oxygen (A/F) sensor connector
- Poor contact in main relay connector
10CA12: CHECK FRONT OXYGEN (A/F) SENSOR.
1. Turn ignition switch to OFF.
Terminals No.2 - No.4:
2. Measure resistance between front oxygen (A/F) sensor connector terminals.
CHECK: Is the resistance less than 10 ohm?
YES: Repair harness and connector.
NOTE: In this case, repair the following:
- Open or ground short circuit in harness between front oxygen (A/F) sensor and ECM connector
- Poor contact in front oxygen (A/F) sensor connector
- Poor contact in ECM connector
NO: Replace front oxygen (A/F) sensor.