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Inspection steps

CAUTION: Before performing troubleshooting, check the fuse for this circuit.
  1. Check if engine is cranked
    1. Check if the engine is cranked.
    RESULT DESCRIPTION

    Result Go to
    Engine is not cranked. A
    Engine is cranked. B

    B: Go to Step  19.

    A: Go to next step

  2. Reading of SSM4 data ([Starter Switch])
    1. Connect the SSM4 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM4.
    4. Select the following menu items using the SSM4.: [Each System]/[Engine Control System]/[Data monitor]/[Starter Switch]
    5. Read [Starter Switch] while the engine is cranked.

    Criteria: Starter signal turns on.

    NG: Go to Step  4.

    OK: Go to next step

  3. Check wiring harness and connector (ST relay - engine control computer - starter ASSY)
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Disconnect the connector for the engine control computer.
    2. Remove the ST relay from the engine compartment relay block.
    3. Disconnect the connector for starter ASSY.
    4. Measure the resistance between the terminals. (For terminal arrangement, refer to ECM TERMINAL ARRANGEMENT .)
    CAUTION: When using tester probes to take measurements at a relay holder, do not push them hard against the holder. Otherwise the holder could be damaged.
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A33-14 (STSW2) - B1-1 Always Less than 1 Ω
    3 (ST relay holder) - B1-1 Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A33-14 (STSW2), B1-1 and 3 (ST relay holder) - other terminals and chassis ground Always 10 k Ω or more

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

  4. Reading of SSM4 data ([Starter cut relay])
    1. Connect the SSM4 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM4.
    4. Select the following menu items using the SSM4.: [Each System]/[Engine Control System]/[Data monitor]/[Starter cut relay]
    5. Read [Starter cut relay] while the engine is cranked.

      Criteria: The starter cut relay turns on.

    RESULT DESCRIPTION

    Result Go to
    Malfunction A
    Normal (Transmission A/T) B
    Normal (Transmission M/T) C

    B: Go to Step  9.

    C: Go to Step  14.

    A: Go to next step

  5. Check wiring harness and connector (engine control computer - ST CUT relay)
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Disconnect the connector for the engine control computer.
    2. Remove the ST CUT relay from the engine compartment relay block.
    3. Measure the resistance between the terminals. (For terminal arrangement, refer to ECM TERMINAL ARRANGEMENT .)
    CAUTION: When using tester probes to take measurements at a relay holder, do not push them hard against the holder. Otherwise the holder could be damaged.
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A35-34 (STAR) - 1 (ST CUT relay holder) Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A35-34 (STAR) and 1 (ST relay holder) - other terminals and chassis ground Always 10 k Ω or more

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

  6. Check wiring harness and connector (IGS relay - ST CUT relay - chassis ground)
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Remove the IGS relay and ST CUT relay from the engine compartment relay block.
    2. Measure the resistance between the terminals.
    CAUTION: When using tester probes to take measurements at a relay holder, do not push them hard against the holder. Otherwise the holder could be damaged.
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    3 (ST CUT relay holder) - 3 (IGS relay holder) Always Less than 1 Ω
    2 (ST CUT relay holder) - 3 (IGS relay holder) Always Less than 1 Ω
    2 (IGS relay holder) - chassis ground Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    3 (ST CUT relay holder), 2 (ST CUT relay holder) and 3 (IGS relay holder) - other terminals and chassis ground Always 10 k Ω or more

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

  7. Check power supply voltage (IGS relay)
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Remove the IGS relay from the engine compartment relay block.
    2. Measure the voltage between the terminals.
    CAUTION: When using tester probes to take measurements at a relay holder, do not push them hard against the holder. Otherwise the holder could be damaged.
    VOLTAGE SPECIFICATION

    Inspection terminals Inspection conditions Standard value
    5 (IGS relay holder) - chassis ground Always 11 to 14 V
    G12586339Courtesy of SUBARU OF AMERICA, INC.

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

  8. Check wiring harness and connector (engine control computer -IG2 relay - IGS relay)
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Disconnect the connector for the engine control computer.
    2. Remove the IG2 relay and IGS relay from the engine compartment relay block.
    3. Measure the resistance between the terminals. (For terminal arrangement, refer to ECM TERMINAL ARRANGEMENT .)
    CAUTION: When using tester probes to take measurements at a relay holder, do not push them hard against the holder. Otherwise the holder could be damaged.
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A33-27 (IGSW) - 3 (IG2 relay holder) Always Less than 1 Ω
    3 (IG2 relay holder) - 1 (IGS relay holder) Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A33-27 (IGSW), 3 (IG2 relay holder) and 1 (IGS relay holder) - other terminals and chassis ground Always 10 k Ω or more

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

    Inspection of smart entry & start system (start function) (Refer to HOW TO PROCEED WITH TROUBLESHOOTING )

  9. Perform a unit inspection of neutral start switch ASSY
    1. Check the neutral start switch ASSY as a single part. (Refer to UNIT INSPECTION )

    NG: Replacement of neutral start switch ASSY (Refer to NEUTRAL START SWITCH ASSY )

    OK: Go to next step

  10. Check wiring harness and connector (smart key computer ASSY - neutral start switch ASSY - INHIBITOR relay)
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Disconnect the connector for neutral start switch ASSY.
    2. Disconnect the connector for smart key computer ASSY.
    3. Remove the INHIBITOR relay from the engine compartment relay block.
    4. Measure the resistance between the terminals.
    CAUTION: When using tester probes to take measurements at a relay holder, do not push them hard against the holder. Otherwise the holder could be damaged.
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    L2-4 - D48-5 (NSW) Always Less than 1 Ω
    L2-4-1 (INHIBITOR relay holder) Always Less than 1 Ω
    L2-5 - chassis ground Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    L2-4, D48-5 (NSW) and 1 (INHIBITOR relay holder) - other terminals and
    chassis ground    		 Always 10 k Ω or more

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

  11. Check wiring harness and connector (ST CUT relay - INHIBITOR relay - ST relay)
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Remove the ST CUT relay, ST relay and INHIBITOR relay from the engine compartment relay block.
    2. Measure the resistance between the terminals.
    CAUTION: When using tester probes to take measurements at a relay holder, do not push them hard against the holder. Otherwise the holder could be damaged.
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    4 (ST CUT relay holder) -2 (INHIBITOR relay holder) Always Less than 1 Ω
    4 (ST CUT relay holder) -5 (INHIBITOR relay holder) Always Less than 1 Ω
    4 (ST CUT relay holder) - 5 (ST relay holder) Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    4 (ST CUT relay holder), 2 (INHIBITOR relay holder), 5 (INHIBITOR relay holder) and 5 (ST relay holder) - other terminals and chassis ground Always 10 k Ω or more

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

  12. Check wiring harness and connector (INHIBITOR relay - ST relay)
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Remove the ST relay and INHIBITOR relay from the engine compartment relay block.
    2. Measure the resistance between the terminals.
    CAUTION: When using tester probes to take measurements at a relay holder, do not push them hard against the holder. Otherwise the holder could be damaged.
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    3 (INHIBITOR relay holder) - 2 (ST relay holder) Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    3 (INHIBITOR relay holder) and 2 (ST relay holder) - other terminals and
    chassis ground    		 Always 10 k Ω or more

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

  13. Check wiring harness and connector (engine control computer - ST relay)
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Disconnect the connector for the engine control computer.
    2. Remove the ST relay from the engine compartment relay block.
    3. Measure the resistance between the terminals. (Refer to ECM TERMINAL ARRANGEMENT for the terminal arrangement)
    CAUTION: When using tester probes to take measurements at a relay holder, do not push them hard against the holder. Otherwise the holder could be damaged.
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A35-26 (STA) - 1 (ST relay holder) Always Less than 1 Ω
    A35-26 (STA) and 1 (ST relay holder) - other terminals and chassis ground Always 10 k Ω or more

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

    Inspection of smart entry & start system (start function) (Refer to HOW TO PROCEED WITH TROUBLESHOOTING )

  14. Perform a unit inspection of clutch start switch ASSY
    1. Check the clutch start switch ASSY as a single part. (Refer to ON-VEHICLE INSPECTION )

    NG: Replacement of clutch start switch ASSY (Refer to CLUTCH PEDAL SWITCH )

    OK: Go to next step

  15. Check clutch start switch ASSY (power supply voltage)
    G12586340Courtesy of SUBARU OF AMERICA, INC.
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Disconnect the connector for clutch start switch ASSY.
    2. Measure the voltage between the terminals.
    VOLTAGE SPECIFICATION

    Inspection terminals Inspection conditions Standard value
    A20-1 - chassis ground Always 11 to 14 V

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

  16. Check wiring harness and connector (clutch start switch ASSY - ST relay - smart key computer ASSY)
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Disconnect the connector for clutch start switch ASSY.
    2. Remove the ST relay from the engine compartment relay block.
    3. Disconnect the connector for smart key computer ASSY.
    4. Measure the resistance between the terminals.
    CAUTION: When using tester probes to take measurements at a relay holder, do not push them hard against the holder. Otherwise the holder could be damaged.
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A20-2 - 2 (ST relay holder) Always Less than 1 Ω
    A20-2 - D48-10 (CLUT) Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A20-2, D48-10 (CLUT) and 2 (ST relay holder) - other terminals and chassis ground Always 10 k Ω or more

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

  17. Check wiring harness and connector (ST relay - ST CUT relay)
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Remove the ST relay and ST CUT relay from the engine compartment relay block.
    2. Measure the resistance between the terminals.
    CAUTION: When using tester probes to take measurements at a relay holder, do not push them hard against the holder. Otherwise the holder could be damaged.
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    5 (ST relay holder) - 4 (ST CUT relay holder) Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    5 (ST relay holder) and 4 (ST CUT relay holder) - other terminals and chassis ground Always 10 k Ω or more

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

  18. Check wiring harness and connector (engine control computer - ST relay)
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Disconnect the connector for the engine control computer.
    2. Remove the ST relay from the engine compartment relay block.
    3. Measure the resistance between the terminals. (Refer to ECM TERMINAL ARRANGEMENT for the terminal arrangement)
    CAUTION: When using tester probes to take measurements at a relay holder, do not push them hard against the holder. Otherwise the holder could be damaged.
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A35-26 (STA) - 1 (ST relay holder) Always Less than 1 Ω
    A33-14 (STSW2) - 3 (ST relay holder) Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A35-26 (STA), A33-14 (STSW2), 1 (ST relay holder), and 3 (ST relay holder) - other terminals and chassis ground Always 10 k Ω or more

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

    Replacement of the engine control computer (Refer to REMOVAL )

  19. Reading of SSM4 data ([Starter Switch])
    1. Connect the SSM4 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM4.
    4. Select the following menu items using the SSM4.: [Each System]/[Engine Control System]/[Data monitor]/[Starter Switch]
    5. Read [Starter Switch] while the engine is cranked.

    Criteria: Starter signal turns on.

    RESULT DESCRIPTION

    Result Go to
    Malfunction A
    Normal B

    B: Go to related circuit inspection listed in symptom table (Refer to SYMPTOM TABLE ).

    A: Go to next step

  20. Check wiring harness and connector (engine control computer - ST relay)
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Disconnect the connector for the engine control computer.
    2. Remove the ST relay from the engine compartment relay block.
    3. Measure the resistance between the terminals. (For terminal arrangement, refer to ECM TERMINAL ARRANGEMENT .)
    CAUTION: When using tester probes to take measurements at a relay holder, do not push them hard against the holder. Otherwise the holder could be damaged.
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A33-14 (STSW2) - 3 (ST relay holder) Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A33-14 (STSW2) and 3 (ST relay holder) - other terminals and chassis
    ground    		 Always 10 k Ω or more

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

    Replacement of the engine control computer (Refer to REMOVAL )

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