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Inspection Procedure

  1. INSPECT ECM (+B VOLTAGE) 
    Fig 1: Locating ECM Connector E5 And E7
    G02917381Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Turn the power switch ON (IG).
    2. Measure the voltage between the specified terminals of the E5 and E7 ECM connectors.

    Standard: 

    VOLTAGE SPECIFICATION

    Tester Connection Specified Condition
    +B (E7-4) - E1 (E5-28) 9 to 14 V

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS TABLE (See  PROBLEM SYMPTOMS TABLE   ) 

    NG: Go To Next Step 

  2. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    Fig 2: Disconnecting ECM E5 Connector
    G02917382Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E5 ECM connector.
    2. Check the resistance between the wire harness side connectors.

      Standard (Check for open): 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      E1 (E5-28) - Body ground Below 1 Ω
    3. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go To Next Step 

  3. INSPECT ECM (IGSW VOLTAGE) 
    Fig 3: Locating ECM Connector E5 And E6
    G02917383Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Turn the power switch ON (IG).
    2. Measure the voltage between the specified terminals of the E5 and E6 ECM connectors.

    Standard: 

    DTC U0293 ECM (IGSW VOLTAGE) STANDARD

    Tester Connection Specified Condition
    IGSW (E6-9) - E1 (E5-28) 9 to 14 V

    OK: Go to step   7 

    NG: Go To Next Step 

  4. CHECK FUSE (IGN FUSE) 
    Fig 4: Locating IGN Fuse
    G02917384Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the IGN fuse from the driver side J/B.
    2. Check the resistance of the IGN fuse.

      Standard: Below 1 Ω 

    3. Reinstall the IGN fuse.

    NG: CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED TO FUSE 

    OK: Go To Next Step 

  5. INSPECT INTEGRATION RELAY(IG2 RELAY) 
    Fig 5: Locating Integration Relay Connector
    G02917385Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the integration relay from the engine room R/B.
    2. Inspect the IG2 relay.

      Standard: 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      (3K-1) - (3I-4) 10 kΩ or higher
      (3K-1) - (3I-4) Below 1 Ω (Apply battery voltage to terminals 3I-2 and 3I-3)
    3. Reinstall the integration relay.

    NG: REPLACE INTEGRATION RELAY 

    OK: Go To Next Step 

  6. CHECK FUSE(AM2 FUSE) 
    Fig 6: Locating AM2 Fuse In Engine Room R/B
    G02917386Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the AM2 fuse from the engine room R/B.
    2. Check the resistance of the AM2 fuse.

      Standard: Below 1 Ω 

    3. Reinstall the AM2 fuse.

    NG: CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED TO FUSE 

    OK: CHECK AND REPAIR HARNESS AND CONNECTOR (BATTERY - IG2 RELAY, IG2 RELAY - ECM) 

  7. INSPECT ECM (MREL VOLTAGE) 
    Fig 7: Locating ECM Connector E5 And E7
    G02917387Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Turn the power switch ON (IG).
    2. Measure the voltage between the specified terminals of the E5 and E7 ECM connectors.

    Standard: 

    VOLTAGE SPECIFICATION

    Tester Connection Specified Condition
    MREL (E7-7) - E1 (E5-28) 9 to 14 V

    NG: REPLACE ECM (See  ENGINE CONTROL SYSTEM  ) 

    OK: Go To Next Step 

  8. CHECK FUSE (EFI FUSE) 
    Fig 8: Locating EFI Fuse In Engine Room R/B
    G02917388Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the EFI fuse from the engine room R/B.
    2. Check the resistance of the EFI fuse.

      Standard: Below 1 Ω 

    3. Reinstall the EFI fuse.

    NG: CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED TO FUSE 

    OK: Go To Next Step 

  9. INSPECT INTEGRATION RELAY (EFI M RELAY) 
    Fig 9: Locating Integration Relay Connector (EFI M Relay
    G02917389Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Remove the integration relay from the engine room R/B.
    2. Inspect the EFI M relay.

      Standard: 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      (3K-1) - (3I-8) 10 kΩ or higher
      (3K-1) - (3I-8) Below 1 Ω (Apply battery voltage to terminals 3I-6 and 3I-7)
    3. Reinstall the integration relay.

    NG: REPLACE INTEGRATION RELAY 

    OK: Go To Next Step 

  10. CHECK HARNESS AND CONNECTOR (EFI M RELAY - ECM, EFI M RELAY - BODY GROUND) 
    Fig 10: Locating ECM Connector In Engine Room R/B
    G02917390Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Check the harness and connectors between the EFI M relay and ECM connector.
      1. Remove the integration relay from the engine room R/B.
      2. Disconnect the E7 ECM connector.
      3. Check the resistance between the wire harness side connectors.

        Standard (Check for open): 

        RESISTANCE SPECIFICATION

        Tester Connection Specified Condition
        EFI M relay (3I-6) - MREL (E7-7) Below 1 Ω
        Fig 11: DISCONNECTING E7 ECM CONNECTOR
        G02917391Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard (Check for short): 

        RESISTANCE SPECIFICATION

        Tester Connection Specified Condition
        EFI M relay (3I-6) or MREL (E7-7) - Body ground 10 kΩ or higher
      4. Reinstall the integration relay.
      5. Reconnect the ECM connector.
    2. Check the harness and the connectors between the EFI M relay and the body ground.
      1. Remove the integration relay from the engine room R/B.
      2. Check the resistance between the wire harness side connector and the body ground.

        Standard (Check for open): 

        RESISTANCE SPECIFICATION

        Tester Connection Specified Condition
        EFI M relay (3I-7) - Body ground Below 1 Ω
      3. Reinstall the integration relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK 

    CHECK AND REPAIR HARNESS AND CONNECTOR (TERMINAL +B OF ECM - BATTERY POS-ITIVE TERMINAL) 

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