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DTC P0130: A/F/O2 Sensor Circuit Bank 1 Sensor 1: Notes

  1. - 

    DTC detecting condition: 

    Immediately at fault recognition

    Wiring diagram: 

    Engine Electrical System. Ref. to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM .

    G13866273Courtesy of SUBARU OF AMERICA, INC.
    CAUTION: Use the check board when measuring the ECM terminal voltage and resistance. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>General Description>PREPARATION TOOL>HOW TO USE CHECK BOARD .
    NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>Basic Diagnostic Procedure>PROCEDURE .
  1. CHECK FRONT OXYGEN (A/F) SENSOR DATA  .
    1. Start the engine and warm up until the engine coolant temperature exceeds 75°C (167°F).
    2. Idle the engine for one minute or more.
    3. Using the Subaru Select Monitor, read the value in [A/F Sensor #11].
      NOTE: For detailed operation procedures, refer to 'Common (Diagnostics)'. Ref. to COMMON (diag)>DATA MONITOR .

    Is the value of [A/F Sensor #11] 1.2 - 3 V?

    Yes  : Go to  2.

    No  : Go to  3.

  2. CHECK FRONT OXYGEN (A/F) SENSOR DATA  .
    1. Race the engine so that the engine speed stays at 3000 rpm. (Five times in total)
    2. Using the Subaru Select Monitor, read the value of [A/F Sensor #11] during racing.
      NOTE:
      • Slowly depress the accelerator pedal to increase engine speed up to 3000 rpm, keep it for approximately 5 seconds, and quickly release the accelerator pedal to decrease engine speed.
      • Normally, the air fuel ratio is rich during racing.
      • For detailed operation procedures, refer to 'Common (Diagnostics)'. Ref. to COMMON (diag)>DATA MONITOR .

    Is the value of [A/F Sensor #11] 2.5 V or more?

    Yes  : Go to  5.

    No  : Go to  3.

  3. CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR (OPEN)  .
    1. Turn the ignition switch to OFF.
    2. Disconnect the connector from ECM.
    3. Disconnect the connector from the front oxygen (A/F) sensor.
    4. Measure the resistance of harness between ECM connector and front oxygen (A/F) sensor connector.

      Connector & terminal 

      (E158) No. 43 - (E24) No. 1:

      (E158) No. 56 - (E24) No. 4:

      (E158) No. 44 - (E24) No. 5:

    Is the resistance less than 1 Ω?

    Yes  : Go to  4.

    No  : Repair the open circuit of harness between ECM connector and front oxygen (A/F) sensor connector  .

  4. CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR (SHORT TO GROUND)  .

    Measure the resistance between the ECM connector and engine ground.

    Connector & terminal 

    (E158) No. 43 - Engine ground:

    (E158) No. 56 - Engine ground:

    (E158) No. 44 - Engine ground:

    Is the resistance 1 MΩ or more?

    Yes  : Go to  5.

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

  5. CHECK EXHAUST SYSTEM  .

    Check exhaust system parts.

    NOTE: Check the following items.
    • Looseness and improper fitting of exhaust system parts
    • Damage (crack, hole etc.) of parts
    • Loose front oxygen (A/F) sensor
    • Loose part and improper installation between front oxygen (A/F) sensor and rear oxygen sensor

    Is there any fault in exhaust system?

    Yes  : Repair or replace faulty parts  .

    No  : Replace the front oxygen (A/F) sensor. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DOTC)>FRONT OXYGEN (A/F) SENSOR .

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