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Home >> Subaru >> 2016 >> BRZ Series.HyperBlue >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Diagnostics - System & Circuit Checks >> Starter System (Models Without Smart Entry & Start System) >> Inspection steps
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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

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

      B: Go to Step  16.

      A: Go to next step

  2. Read SSM3 data ([starter switch])
    1. Connect the SSM3 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM3.
    4. Select the following menu items using the SSM3. [Inspection of BRZ]/[Each System Check]/[Engine Control System]/[Current Data Display & Save]/[Starter Switch]
    5. Read [Starter Switch] when the ignition switch is operated.

      Criteria

      CRITERIA SPECIFICATION

      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 assembly)
    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 assembly.
    3. Remove the ST relay from the engine compartment relay block.
    4. 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.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (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

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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 assembly
    1. Check the ignition OR starter switch assembly as a single part. (refer to INSTALLATION )

      NG: Replacement of ignition or starter switch assembly (refer to IGNITION (STARTER) SWITCH ASSEMBLY )

      OK: Go to next step

  5. Check wiring harness and connector (ignition OR starter switch assembly - 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 assembly.
    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.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (OPEN CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      D55-8 (ST2) - 5 (ST relay holder) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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 Ωor more

      NG: Repair or replacement of wiring harness or connector

      OK: Go to next step

  6. Check power supply voltage (ignition OR starter switch assembly)
    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 assembly.
    2. Measure the voltage between the terminals.

      Voltage

      VOLTAGE REFERENCE

      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
      Fig 1: Ignition Or Starter Switch Assembly Connector End View (D55)
      G10212967Courtesy of SUBARU OF AMERICA, INC.

      Result

      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: Repair or replacement of wiring harness or connector

  7. Perform a unit inspection of neutral start switch assembly
    1. Check the neutral start switch assembly as a single part. (refer to UNIT INSPECTION )

      NG: Replacement of neutral start switch assembly (refer to NEUTRAL START SWITCH ASSEMBLY )

      OK: Go to next step

  8. Check wiring harness and connector (neutral start switch assembly - 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 assembly.
    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.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (OPEN CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      L2-4-1 (INHIBITOR relay holder) Always Less than 1 Ω
      L2-5 - chassis ground Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (SHORT CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      L2-4 and 1 (INHIBITOR relay holder) - other terminals and chassis ground Always 10 k Ωor 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 assembly - 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 assembly.
    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.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (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

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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 Ωor 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.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (OPEN CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      3 (INHIBITOR relay holder) - 2 (ST relay holder) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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 Ωor 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. (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.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (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

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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 Ωor more

      NG: Repair or replacement of wiring harness or connector

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

  12. Perform a unit inspection of clutch start switch assembly
    1. Check the clutch start switch assembly as a single part. (refer to ON-VEHICLE INSPECTION )

      NG: Replacement of clutch start switch assembly (refer to CLUTCH PEDAL SWITCH )

      OK: Go to next step

  13. Check wiring harness and connector (ignition OR starter switch assembly - clutch start switch assembly)
    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 assembly.
    2. Disconnect the connector for clutch start switch assembly.
    3. Measure the resistance between the terminals.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (OPEN CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      D55-1 (ST1) - A20-1 Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (SHORT CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      D55-1 (ST1) and A20-1 - other terminals and chassis ground Always 10 k Ωor more

      NG: Repair or replacement of wiring harness or connector

      OK: Go to next step

  14. Check wiring harness and connector (clutch start switch assembly - 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 assembly 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.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (OPEN CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      A20-2 - 2 (ST relay holder) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (SHORT CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      A20-2 and 2 (ST relay holder) - other terminals and chassis ground Always 10 k Ωor 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. (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.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (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

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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 Ωor more

      NG: Repair or replacement of wiring harness or connector

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

  16. Read SSM3 data ([starter switch])
    1. Connect the SSM3 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn on the SSM3.
    4. Select the following menu items using the SSM3. [Inspection of BRZ]/[Each System Check]/[Engine Control System]/[Current Data Display & Save]/[Starter Switch]
    5. Read [Starter Switch] when the ignition switch is operated.

      Criteria

      CRITERIA SPECIFICATION

      Inspection conditions Starter signal
      IG ON OFF
      Cranking ON

      Result

      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. (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.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (OPEN CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      A33-17 (STSW) - 3 (ST relay holder) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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 Ωor more

      NG: Repair or replacement of wiring harness or connector

      OK: Replacement of the engine control computer (refer to REMOVAL )

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