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Inspection steps

CAUTION: Before performing troubleshooting, check the fuse for this circuit.
  1. Perform SSM3 [System Operation Check Mode] ([Control the Fuel Pump Duty])
    1. Connect the SSM3 to the DLC3.
    2. Turn the ignition switch to ON.
    3. Select the following menu items using the SSM3.: [Inspection of BRZ]/[Each System Check]/[Engine Control System]/[Work Support]/[System Operation Check Mode]/[Control the Fuel Pump Duty]
    4. Check the operating sound of the fuel pump (low pressure side) when [System Operation Check Mode] is performed.

      Criteria

      RESISTANCE REFERENCE (SHORT CIRCUIT CHECK)

      [Control the Fuel Pump Duty] Criteria
      20 % and 80 % Operating sound is heard.
      OFF Operating sound is not heard.

      NG: Go to Step  8.

      OK: Go to next step

  2. Perform SSM3 [System Operation Check Mode] ([Control the Fuel Pump Duty])
    1. Remove the fuel tank assembly. (refer to REMOVAL )
    2. Remove the fuel pump assembly (low pressure side) from the fuel tank assembly.
    3. Completely remove the remaining fuel from the fuel pump assembly (low pressure side).
    4. Install the connector for the fuel pump assembly (low pressure side).
      WARNING: Check that no fuel remains inside or around the fuel pump assembly.
    5. Connect the SSM3 to the DLC3.
    6. Turn the ignition switch to ON.
    7. Select the following menu items using the SSM3.: [Inspection of BRZ]/[Each System Check]/[Engine Control System]/[Work Support]/[System Operation Check Mode]/[Control the Fuel Pump Duty]
    8. Measure the voltage between each terminal when [System Operation Check Mode] is performed.

      Voltage

      VOLTAGE REFERENCE

      Inspection terminals Inspection conditions Standard value
      3 - 4 Fuel pump duty: 25% 3.2 to 4.05 V
      3 - 4 Fuel pump duty: 80% 8.8 to 12.5 V
      Fig 1: Fuel Pump Assembly (Low Pressure Side) Connector Terminal Identification
      G10212960Courtesy of SUBARU OF AMERICA, INC.
    9. Select the following menu items using the SSM3.: [Inspection of BRZ]/[Each System Check]/[Engine Control System]/[Work Support]/[System Operation Check Mode]/[Control the Fuel Pump Duty]
    10. Measure the voltage between each terminal when [System Operation Check Mode] is performed.

      Voltage

      VOLTAGE REFERENCE

      Inspection terminals Inspection conditions Standard value
      3 - 4 Fuel pump duty: 90 % 9.0 to 14.0 V
      NOTE:
      • Measure the voltage with all connectors connected.
      • Before performing this inspection, check that the battery voltage is 11 to 14 V (battery not discharged).

      NG: Go to Step  6.

      OK: Go to next step

  3. Check wiring harness and connector (engine control computer - fuel pump control 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 the engine control computer.
    2. Disconnect the connector for the fuel pump control computer assembly.
    3. Measure the resistance between the terminals. (Refer to ECM TERMINAL ARRANGEMENT for the terminal arrangement)

      Resistance (open circuit check)

      RESISTANCE REFERENCE (OPEN CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      A35-19 (FPC) - G12-2 (FPC) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (SHORT CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      A35-19 (FPC) and G12-2 (FPC) - other terminals and chassis ground Always 10 k Ωor more

      NG: Repair or replacement of wiring harness or connector

      OK: Go to next step

  4. Replacement of fuel pump assembly (low pressure side)
    1. Replace the fuel pump assembly (low pressure side). (refer to REMOVAL )

      Next

  5. Check trouble symptom
    1. Check whether the trouble symptom is improved or not.

      Result

      Result Go to
      Symptom is improved. A
      Symptom is not improved. B

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

      A: Complete

  6. Replacement of the fuel pump control computer assembly
    1. Replace the fuel pump control computer assembly. (refer to REMOVAL )

      Next

  7. Check trouble symptom
    1. Check whether the trouble symptom is improved or not.

      Result

      Result Go to
      Symptom is improved. A
      Symptom is not improved. B

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

      A: Complete

  8. Check fuel pump control computer assembly (input 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 the fuel pump control computer assembly.
    2. Turn the ignition switch to ON.
    3. Measure the voltage between the terminals.

      Voltage

      VOLTAGE REFERENCE

      Inspection terminals Inspection conditions Standard value
      G12-1 (+B) - chassis ground IG ON 11 to 14 V
      Fig 2: Fuel Pump Control Computer Assembly Connector End View (G12)
      G10212961Courtesy of SUBARU OF AMERICA, INC.

      NG: Go to Step  14.

      OK: Go to next step

  9. Check wiring harness and connector (fuel pump assembly - fuel pump control 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 the fuel pump assembly (low pressure side).
    2. Disconnect the connector for the fuel pump control computer assembly.
    3. Measure the resistance between the terminals.

      Resistance (open circuit check)

      RESISTANCE REFERENCE (OPEN CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      G7-4 (FP-) - G12-5 (FP-) Always Less than 1 Ω
      G7-3 (FP+) - G12-6 (FP+) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (SHORT CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      G7-4 (FP-) and G12-5 (FP-) - other terminals and chassis ground Always 10 k Ω or more
      G7-3 (FP+) and G12-6 (FP+) - 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. Perform a unit inspection of fuel pump assembly (low pressure side)
    1. Perform a unit inspection on the fuel pump (low-pressure side) (refer to UNIT INSPECTION )

      NG: Replacement of the fuel pump assembly (low-pressure side) (refer to REMOVAL )

      OK: Go to next step

  11. Check wiring harness and connector (fuel pump control computer assembly - engine control computer)
    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 the fuel pump control computer assembly.
    3. Measure the resistance between the terminals. (Refer to ECM TERMINAL ARRANGEMENT for the terminal arrangement)

      Resistance (open circuit check)

      RESISTANCE REFERENCE (OPEN CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      A35-19 (FPC) - G12-2 (FPC) Always Less than 1 Ω
      G12-4 (E) - chassis ground Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (SHORT CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      A35-19 (FPC) and G12-2 (FPC) - 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. Replacement of the fuel pump control computer assembly
    1. Replace the fuel pump control computer assembly. (refer to REMOVAL )
  13. Check trouble symptom
    1. Check whether the trouble symptom is improved or not.

      Result

      Result Go to
      Symptom is improved. A
      Symptom is not improved. B

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

      A: Complete

  14. Check wiring harness and connector (C/OPEN relay - fuel pump control 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. Remove the C/OPEN relay from the engine compartment relay block.
    2. Disconnect the connector for the fuel pump control computer assembly.
    3. Measure the resistance between the terminals.
      CAUTION: When using tester probes to take measurements at a 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 (C/OPEN relay holder) - G12-1 (+B) Always Less than 1 Ω
      2 (C/OPEN 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 (C/OPEN relay holder) and G12-1 (+B) - 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 power supply voltage (C/OPEN relay)
    NOTE: refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM for inspection procedure and precautions of wiring harness and connector.
    1. Remove the C/OPEN relay from the engine compartment relay block.
    2. Measure the resistance between the terminals.
      CAUTION: When using tester probes to take measurements at a holder, do not push them hard against the holder. Otherwise the holder could be damaged. Resistance (open circuit check)
      Inspection terminals Inspection conditions Standard value
      5 (C/OPEN relay holder) - chassis ground Always 11 to 14 V
      Fig 3: Locating C/OPEN Relay Holder On Engine Compartment Relay Block
      G10212962Courtesy of SUBARU OF AMERICA, INC.

      NG: Inspection of the ECM power supply system (Refer to ECM POWER SUPPLY SYSTEM  )

      OK: Go to next step

  16. Check wiring harness and connector (C/OPEN relay engine control computer - IG2 relay)
    NOTE: refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM for inspection procedure and precautions of wiring harness and connector.
    1. Disconnect the connector for the engine control computer.
    2. Remove the C/OPEN relay and IG2 relay from the engine compartment relay block.
    3. Measure the resistance between the terminals.
      CAUTION: When using tester probes to take measurements at a 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
      1 (C/OPEN relay holder) - A33-27 (IGSW) Always Less than 1 Ω
      1 (C/OPEN relay holder) - 3 (IG2 relay holder) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (SHORT CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      1 (C/OPEN relay holder), A33-27 (IGSW) and 3 (IG2 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 )

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