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Inspection steps

CAUTION: Before performing troubleshooting, check the fuse for this circuit.
  1. Check if engine is cranked
    1. Operate the ignition switch to check if the engine is cranked or not.
    RESULT DESCRIPTION

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

    B: Go to Step  16.

    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] when the ignition switch is operated.
    INSPECTION CONDITION - CRITERIA

    Inspection conditions Starter signal
    IG ON OFF
    Cranking ON

    NG: Go to Step  4.

    OK: Go to next step

  3. Check wiring harness and connector (engine control computer - ST relay - 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. Disconnect the connector for starter ASSY.
    3. Remove the ST relay from the engine compartment relay block.
    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
    B1-1 - A33-17 (STSW) Always Less than 1 Ω
    B1-1 - 3 (ST relay holder) Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A33-17 (STSW), 3 (ST relay holder), and B1-1 - 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. Perform a unit inspection of ignition OR starter switch ASSY
    1. Check the ignition OR starter switch ASSY as a single part. (Refer to UNIT INSPECTION )

    NG: Replacement of ignition or starter switch ASSY (Refer to IGNITION (STARTER) SWITCH ASSY )

    OK: Go to next step

  5. Check wiring harness and connector (ignition OR starter switch ASSY - 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 ignition OR starter switch ASSY.
    2. Remove the ST relay from the engine compartment relay block.
    3. 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
    D55-8 (ST2) - 5 (ST relay holder) Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    D55-8 (ST2) 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

  6. Check power supply voltage (ignition OR starter switch ASSY)
    G12586342Courtesy 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 the ignition OR starter switch ASSY.
    2. Measure the voltage between the terminals.
    VOLTAGE SPECIFICATION

    Inspection terminals Inspection conditions Standard value
    D55-2 (AM1) - chassis ground Always 11 to 14 V
    D55-7 (AM2) - chassis ground Always 11 to 14 V
    RESULT DESCRIPTION

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

    B: Go to Step  7.

    C: Go to Step  12.

    A: Go to next step

    Repair or replacement of wiring harness or connector

  7. 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

  8. Check wiring harness and connector (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. Remove the INHIBITOR relay from the engine compartment relay block.
    3. 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
    L2-4-1 (INHIBITOR relay holder) Always Less than 1 Ω
    L2-9 - chassis ground Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    L2-4 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

  9. Check wiring harness and connector (ignition OR starter 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 the ignition OR starter switch ASSY.
    2. Remove the INHIBITOR relay from the engine compartment relay block.
    3. 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
    D55-1 (ST1) - 5 (INHIBITOR relay holder) Always Less than 1 Ω
    D55-1 (ST1) - 2 (INHIBITOR relay holder) Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    D55-1 (ST1), 2 (INHIBITOR relay holder) and 5 (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

  10. 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 INHIBITOR relay and ST 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

  11. 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
    A35-26 (STA) - 1 (ST relay holder) Always Less than 1 Ω
    A33-17 (STSW) - 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), A33-17 (STSW), 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

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

  12. 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

  13. Check wiring harness and connector (ignition OR starter switch ASSY - clutch start switch 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 ignition OR starter switch ASSY.
    2. Disconnect the connector for clutch start switch ASSY.
    3. Measure the resistance between the terminals.
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    D55-1 (ST1) - A20-1 Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    D55-1 (ST1) and A20-1 - 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

  14. Check wiring harness and connector (clutch start switch ASSY - 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 clutch start switch ASSY connector.
    2. Remove the ST relay from the engine compartment relay block.
    3. 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
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A20-2 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

  15. 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
    A35-26 (STA) - 1 (ST relay holder) Always Less than 1 Ω
    A33-17 (STSW) - 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), A33-17 (STSW), 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

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

  16. 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] when the ignition switch is operated.
    INSPECTION CONDITION - CRITERIA

    Inspection conditions Starter signal
    IG ON OFF
    Cranking 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

  17. 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
    A33-17 (STSW) - 3 (ST relay holder) Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    A33-17 (STSW) 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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