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Inspection Procedure

  1. INSPECT HV CONTROL ECU (+B, +B1 VOLTAGE) 
    1. Turn the ignition switch to the ON position.
    2. Measure the voltage between the terminals of the H34 and H31 HV control ECU connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      +B1 (H34-2) - E1 (H31-5) 9 to 14 V
      +B2 (H34-1) - E1 (H31-5) 9 to 14 V
      3. Fig 1: Identifying Terminals Of H34 And H31 HV Control ECU Connectors
      G05858377Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN  PROBLEM SYMPTOMS TABLE  

    NG: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (HV CONTROL ECU - BODY GROUND) 
    1. Disconnect the H31 HV control ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      E1 (H31-5) - Body ground Below 1 Ω
    3. Reconnect the HV control ECU connector.
      4. Fig 2: Identifying Terminals Of H31 HV Control ECU Connector
      G05275738Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. INSPECT HV CONTROL ECU (IGSW VOLTAGE) 
    1. Turn the ignition switch to the ON position.
    2. Measure the voltage between the terminals of the H29 and H31 HV control ECU connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      IGSW (H29-9) - E1 (H31-5) 9 to 14 V
      3. Fig 3: Identifying Terminals Of H29 And H31 HV Control ECU Connectors
      G05275739Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to step  6

    NG: Go to next step 

  4. CHECK FUSE (IGN FUSE) 
    1. Remove the IGN fuse from the instrument panel J/B.
    2. Measure the IGN fuse resistance.

      Standard resistance: Below 1 Ω 

    3. Reinstall the IGN fuse.
      4. Fig 4: Identifying IGN Fuse
      G05275740Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    OK: Go to next step 

  5. INSPECT IGNITION SWITCH ASSEMBLY 
    1. Check for continuity between the connector terminals shown in the table below.

      Standard 

      TERMINALS CONTINUITY REFERENCE

      Switch Terminal No. Resistance
      LOCK All Terminals No continuity
      ACC 1 - 2 Continuity
      ON 2 - 3, 2 - 4, 3 - 4, 6 - 7 Continuity
      START 1 - 2, 1 - 4, 2 - 4, 6 - 7, 6 - 8, 7 - 8 Continuity
      Fig 5: Identifying Terminals Of Ignition Switch Assembly Connector
      G05275741Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE IGNITION SWITCH ASSEMBLY 

    OK: CHECK AND REPLACE HARNESS AND CONNECTOR (IGNITION SWITCH ASSEMBLY - HV CONTROL ECU) 

  6. INSPECT HV CONTROL ECU (MREL VOLTAGE) 
    1. Turn the ignition switch to the ON position.
    2. Measure the voltage between the terminals of the H34 and H31 HV control ECU connectors.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      MREL (H34-12) - E1 (H31-5) 9 to 14 V
      3. Fig 6: Identifying Terminals Of H34 And H31 HV Control ECU Connectors
      G05275742Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE HV CONTROL ECU 

    OK: Go to next step 

  7. CHECK FUSE (IGCT NO. 2 FUSE) 
    1. Remove the IGCT No. 2 fuse from the R/B No. 3.
    2. Measure the IGCT No. 2 fuse resistance.

      Standard resistance: Below 1 Ω 

    3. Reinstall the IGCT No. 2 fuse.
      4. Fig 7: Identifying IGCT No. 2 Fuse
      G05200203Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    OK: Go to next step 

  8. INSPECT IGCT RELAY 
    1. Remove the IGCT relay from the engine room R/B.
    2. Measure the IGCT relay resistance.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      3 - 5 10 kΩ or higher
      Below 1 Ω (Apply battery voltage between terminals 1 and 2)
      3. Fig 8: Measuring IGCT Relay Resistance
      G04975584Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE IGCT RELAY 

    OK: Go to next step 

  9. CHECK HARNESS AND CONNECTOR (IGCT RELAY- HV CONTROL ECU, IGCT RELAY - BODY GROUND) 
    1. Check the harness and the connectors between the integration relay and the HV control ECU.
      1. Remove the IGCT relay from the engine room R/B.
      2. Disconnect the H34 HV control ECU connector.
      3. Measure the resistance according to the value(s) in the table below.

        Standard resistance (Check for open) 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        IGCT relay (1) - MREL (H34-12) Below 1 Ω

        Standard resistance (Check for short) 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        IGCT relay (1) or MREL (H34-12) - Body ground 10 kΩ or higher
    2. Check the harness and the connectors between the IGCT relay and body ground.
      1. Remove the IGCT relay from the engine room R/B.
      2. Measure the resistance according to the value(s) in the table below.

        Standard resistance (Check for open) 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Specified condition
        IGCT relay (2) - Body ground Below 1 Ω
      3. Fig 9: Identifying Terminals Of H34 HV Control ECU Connector
      G05275745Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: CHECK AND REPAIR HARNESS AND CONNECTOR (TERMINAL +B OF HV CONTROL ECU - BATTERY POSITIVE TERMINAL) 

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