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Home >> Subaru >> 2019 >> BRZ Series.Gray >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostics) (2 Of 3) >> EFI System (FA20) >> DTC P0512: Starter Switch Circuit High input; DTC P0616: Starter Relay Circuit Low; DTC P0617: Starter Relay Circuit High; DTC P081A: Starter Cut Relay System Circuit (Low) >> Description of functions >> Inspection steps
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Inspection steps

CAUTION: Before performing troubleshooting, check the fuse for this circuit.
NOTE: Read the freeze frame data using the SSM4. A part of the engine running conditions under which the engine trouble occurred is recorded in the freeze frame data, which is useful for troubleshooting.
  1. 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].
    VOLTAGE SPECIFICATION

    Item name Inspection conditions Standard value
    [Starter Switch] IG ON OFF
    When cranking ON
    RESULT DESCRIPTION

    Result Go to
    Abnormal (models without smart entry & start system) A
    Abnormal (models with smart entry & start system) B
    Normal C

    A: Go to next step

    B: Go to Step  4.

    C: Go to Step  9.

  2. Relay unit inspection (ST relay)
    1. Perform ST relay unit inspection. (Refer to RELAY )

    NG: Relay replacement (ST relay)

    OK: Go to next step

  3. Check wiring harness and connector (ST relay - engine control computer)
    NOTE: Refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM or inspection procedure and precautions of wiring harness and connector.
    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 .)
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    3 (ST relay holder) - A33-17 (STSW2) Always Less than 1 Ω
    1 (ST relay holder) - A35-26 (STA) Always Less than 1 Ω
    STANDARD VALUE RESISTANCE SPECIFICATION (SHORT CIRCUIT CHECK)

    Inspection terminals Inspection conditions Standard value
    3 (ST relay holder) and A33-17 (STSW2) - other terminals and chassis
    ground    		 Always 10 k Ωor more
    1 (ST relay holder) and A35-26 (STA) - other terminals and chassis ground Always 10 k Ωor more
    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.

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

    Starter system check (models without smart entry & start system) (Refer to STARTER SYSTEM (MODELS WITHOUT SMART ENTRY & START SYSTEM) )

  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].
    VOLTAGE SPECIFICATION

    Item name Inspection conditions Standard value
    [Starter cut relay] IG ON OFF
    When cranking ON

    NG: Go to Step  7.

    OK: Go to next step

  5. Relay unit inspection (ST relay)
    1. Perform ST relay unit inspection. (Refer to RELAY )

    NG: Relay replacement (ST relay)

    OK: Go to next step

  6. Check wiring harness and connector (ST relay - engine control computer)
    NOTE: Refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM or inspection procedure and precautions of wiring harness and connector.
    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 .)
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

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

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

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

    Starter system check (models with smart entry & start system) (Refer to STARTER SYSTEM (MODELS WITH SMART ENTRY & START SYSTEM) )

  7. Relay unit inspection (ST CUT relay)
    1. Perform ST CUT relay unit inspection. (Refer to RELAY )

    NG: Relay replacement (ST CUT relay)

    OK: Go to next step

  8. Check wiring harness and connector (ST CUT relay - engine control computer)
    NOTE: Refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM or inspection procedure and precautions of wiring harness and connector.
    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 .)
    STANDARD VALUE RESISTANCE SPECIFICATION (OPEN CIRCUIT CHECK)

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

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

    NG: Repair or replacement of wiring harness or connector

    OK: Go to next step

    Starter system check (models with smart entry & start system) (Refer to STARTER SYSTEM (MODELS WITH SMART ENTRY & START SYSTEM) )

  9. Clear DTC
    1. Connect the SSM4 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM4.
    4. Follow the SSM4 on-screen instructions to clear the DTCs. (Refer to CHECKING/CLEARING DTC )
    5. Turn the ignition switch to OFF, and wait for 30 seconds.
  10. Perform test drive for operation check
    1. Perform test drive. (Refer to "TEST DRIVE " under "Description of functions")
    2. Follow the SSM4 on-screen instructions to check the DTC. (Refer to CHECKING/CLEARING DTC )
    Result Go to
    No DTC is output A
    P0512, P0616, P0617, or P081A is output. B

    A: Go to next step

    B: Replacement of the engine control computer (Refer to REMOVAL )

    Inspection for problems that do not normally occur (Refer to INSPECTION FOR PROBLEMS THAT DO NOT NORMALLY OCCUR )

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