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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 With 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. Check if the engine is cranked.

      Result

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

      B: Go to Step  19.

      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] 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 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. Remove the ST relay from the engine compartment relay block.
    3. Disconnect the connector for starter assembly.
    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
      A33-14 (STSW2) - B1-1 Always Less than 1 Ω
      3 (ST relay holder) - B1-1 Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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. Read SSM3 data ([starter cut relay])
    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 cut relay]
    5. Read [Starter cut relay] while the engine is cranked.

      Criteria: The starter cut relay turns on.

      Result

      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. (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
      A35-34 (STAR) - 1 (ST CUT relay holder) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (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

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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 Ωor 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

      VOLTAGE REFERENCE

      Inspection terminals Inspection conditions Standard value
      5 (IGS relay holder) - chassis ground Always 11 to 14 V
      Fig 1: Locating IGS Relay Holder On Engine Compartment Relay Block
      G10212964Courtesy 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. (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
      A33-27 (IGSW) - 3 (IG2 relay holder) Always Less than 1 Ω
      3 (IG2 relay holder) - 1 (IGS relay holder) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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: Check smart entry & start system (start function) (refer to HOW TO PROCEED WITH TROUBLESHOOTING )

  9. 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

  10. Check wiring harness and connector (smart key computer assembly - 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. Disconnect the connector for smart key computer assembly.
    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.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (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

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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 Ωor 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.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (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

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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 Ωor 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.

      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

  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.

      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

      Resistance (short circuit check)

      RESISTANCE REFERENCE (SHORT CIRCUIT CHECK)

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

      NG: Repair or replacement of wiring harness or connector

      OK: Check smart entry & start system (start function) (refer to HOW TO PROCEED WITH TROUBLESHOOTING )

  14. 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

  15. Check clutch start switch assembly (power supply voltage)
    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 assembly.
    2. Measure the voltage between the terminals.

      Voltage

      VOLTAGE REFERENCE

      Inspection terminals Inspection conditions Standard value
      A20-1 - chassis ground Always 11 to 14 V
      Fig 2: Clutch Start Switch Assembly Connector End View (A20)
      G10212965Courtesy of SUBARU OF AMERICA, INC.

      NG: Repair or replacement of wiring harness or connector

      OK: Go to next step

  16. Check wiring harness and connector (clutch start switch assembly - ST relay - smart key computer 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 clutch start switch assembly.
    2. Remove the ST relay from the engine compartment relay block.
    3. Disconnect the connector for smart key computer assembly.
    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.

      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
      A20-2 - D48-10 (CLUT) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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 Ωor 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.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (OPEN CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      5 (ST relay holder) - 4 (ST CUT relay holder) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (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 Ωor 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.

      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
      A33-14 (STSW2) - 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), A33-14 (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: Replacement of the engine control computer (refer to REMOVAL )

  19. 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] while the engine is cranked.

      Criteria: Starter signal turns 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

  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. (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
      A33-14 (STSW2) - 3 (ST relay holder) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (SHORT CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      A33-14 (STSW2) 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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