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Inspection steps

CAUTION: Before performing troubleshooting, check the fuse for this circuit.
  1. Check engine control computer (inspection of +B and +B2 voltages)
    NOTE: For the inspection procedure and precautions for wiring harnesses and connectors, refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM .
    1. Turn the ignition switch to ON.
    2. Measure the voltage between the terminals. (Refer to ECM TERMINAL ARRANGEMENT for the terminal arrangement)

      Voltage

      VOLTAGE REFERENCE

      Inspection terminals Inspection conditions Standard value
      A34-6(+B) - A36-4(E01) IG ON 12 to 14 V
      A33-1 (+B2) - A36-4 (B01) IG ON 12 to 14 V
      Fig 1: Engine Control Computer Connector Terminal Identification
      G10212976Courtesy of SUBARU OF AMERICA, INC.

      NG: Go to Step  4.

      OK: Go to next step

  2. Check wiring harness and connector (engine control computer - chassis ground)
    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. 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 Criteria
      A36-4 (E01) - chassis ground Always Less than 1 Ω
    3. Connect the connector for engine control computer.

      NG: Repair or replacement of wiring harness or connector

      OK: Go to next step

  3. Check engine control computer (IGSW voltage)
    NOTE: refer to INSPECTION PROCEDURES FOR ELECTRICAL CIRCUITS AND HOW TO PERFORM for inspection procedure and precautions of wiring harness and connector.
    1. Turn the ignition switch to ON.
    2. Measure the voltage between the terminals. (Refer to ECM TERMINAL ARRANGEMENT for the terminal arrangement)

      Voltage

      VOLTAGE REFERENCE

      Inspection terminals Inspection conditions Standard value
      A33-27(IGSW) - A36-4(E01) IG ON 10 to 13 V
      Fig 2: Engine Control Computer Connector Terminal Identification
      G10212977Courtesy of SUBARU OF AMERICA, INC.

      NG: Go to Step  8.

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

  4. Check engine control computer (SSHUT 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. Turn the ignition switch to ON.
    2. Measure the voltage between the terminals. (Refer to ECM TERMINAL ARRANGEMENT for the terminal arrangement)

      Voltage

      VOLTAGE REFERENCE

      Inspection terminals Inspection conditions Standard value
      A35-13(SSHUT) - A36-4(E01) IG ON Approx. 0 V
      Fig 3: Engine Control Computer Connector Terminal Identification
      G10212978Courtesy of SUBARU OF AMERICA, INC.

      NG: Repair or replacement of wiring harness or connector

      OK: Go to next step

  5. Relay unit inspection (EFI MAIN1 relay)
    1. Perform unit inspection of EFI MAIN1 relay. (refer to RELAY )

      NG: Relay replacement (EFI MAIN1 relay)

      OK: Go to next step

  6. Check wiring harness and connector (EFI MAIN1 relay - engine control computer)
    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 EFI MAIN1 relay from the engine compartment relay block.
    2. Disconnect the connector for the engine control computer.
    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
      1 (EFI MAIN1 relay holder) - A35-13 (SSHUT) Always Less than 1 Ω
      3 (EFI MAIN1 relay holder) - A34-6 (+B) Always Less than 1 Ω
      3 (EFI MAIN1 relay holder) - A33-1 (+B2) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (SHORT CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      1 (EFI MAIN1 relay holder) and A35-13 (SSHUT) - other terminals and chassis ground Always 10 k Ωor more
      3 (EFI MAIN1 relay holder), A34-6 (+B) and A33-1 (+B2) - 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 (EFI MAIN1 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 EFI MAIN1 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
      2 (EFI MAIN1 relay holder) - chassis ground Always 11 to 14 V
      5 (EFI MAIN1 relay holder) - chassis ground Always 11 to 14 V
      Fig 4: Locating EFI MAIN1 Relay Holder On Engine Compartment Relay Block
      G10212979Courtesy 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 (IG2 relay - 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. Remove the IG2 relay from the engine compartment relay block.
    2. Disconnect the connector for the engine control computer.
    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
      3 (IG2 relay holder) - A33-27 (IGSW) Always Less than 1 Ω
      1 (IG2 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 (IG2 relay holder) and A33-27 (IGSW) - 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. Perform a unit inspection of relay (IG2 relay)
    1. Check IG2 relay as a single part. (refer to RELAY )

      NG: Relay replacement (IG2 relay)

      OK: Go to next step

  10. Check power supply voltage (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. Remove the IG2 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 (IG2 relay holder) - chassis ground Always 11 to 14 V
      Fig 5: Locating IG2 Relay Holder On Engine Compartment Relay Block
      G10212980Courtesy of SUBARU OF AMERICA, INC.

      Result

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

      B: Go to Step 11.

      C: Go to Step  12.

      A: Repair or replacement of wiring harness or connector

  11. Check wiring harness and connector (IG2 relay - smart key computer assembly)
    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 IG2 relay from the engine compartment relay block.
    2. Disconnect the connector for smart key computer assembly.
    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
      2 (IG2 relay holder) - D48-9 (IG2D) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (SHORT CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      2 (IG2 relay holder) and D48-9 (IG2D) - other terminals and chassis ground Always 10 k Ωor more

      NG: Repair or replacement of wiring harness or connector

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

  12. Check wiring harness and connector (IG2 relay - ignition OR starter switch assembly)
    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 IG2 relay from the engine compartment relay block.
    2. Disconnect the connector for the ignition OR starter switch assembly.
    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
      2 (IG2 relay holder) - D55-6 (IG2) Always Less than 1 Ω

      Resistance (short circuit check)

      RESISTANCE REFERENCE (SHORT CIRCUIT CHECK)

      Inspection terminals Inspection conditions Standard value
      2 (IG2 relay holder) and D55-6 (IG2) - 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. 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: Repair or replacement of wiring harness or connector

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