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Inspection Procedure

  1. INSPECT HYBRID VEHICLE CONTROL ECU (+B1, +B2 VOLTAGE) 
    1. Turn the power switch on (IG).
    2. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

    TESTER CONNECTION SPECIFIED CONDITION

    Tester Connection Condition Specified Condition
    A43-2 (+B1) - B3-5 (E1) Always 11 to 14 V
    A43-1 (+B2) - B3-5 (E1) Always 11 to 14 V
    Fig 1: Identifying Hybrid Vehicle Control ECU (+B1, +B2 Voltage)
    G05625674Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step   2

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

  2. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - BODY GROUND) 
    1. Disconnect the hybrid vehicle control ECU connector.
      Fig 2: Identifying Hybrid Vehicle Control ECU Connector
      G05625675Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance (Check for open) 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      B3-5 (E1) - Body ground Always Below 1 Ω
    3. Reconnect the hybrid vehicle control ECU connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (HYBRID VEHICLE CONTROL ECU - BODY GROUND) 

    OK: Go to Next Step 

  3. INSPECT HYBRID VEHICLE CONTROL ECU (IGSW VOLTAGE) 
    1. Turn the power switch on (IG).
    2. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

    TESTER CONNECTION SPECIFIED CONDITION

    Tester Connection Condition Specified Condition
    D35-9 (IGSW) - B3-5 (E1) Always 11 to 14 V
    Fig 3: Identifying Hybrid Vehicle Control ECU (IGSW Voltage)
    G05625676Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step  9

    OK: Go to Next Step 

  4. INSPECT HYBRID VEHICLE CONTROL ECU (MREL VOLTAGE) 
    1. Turn the power switch on (IG).
    2. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

    TESTER CONNECTION SPECIFIED CONDITION

    Tester Connection Condition Specified Condition
    A43-12 (MREL) - B3-5 (E1) Always 11 to 14 V
    Fig 4: Identifying Hybrid Vehicle Control ECU (MREL Voltage)
    G05625677Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step   5

    OK: REPLACE HYBRID VEHICLE CONTROL ECU 

  5. CHECK FUSE (IGCT NO. 2 FUSE) 
    1. Remove the IGCT No. 2 fuse from the engine room relay block No. 2.
      Fig 5: Identifying IGCT No. 2 Fuse
      G05625678Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the IGCT No. 2 fuse resistance.

      Standard resistance: Below 1 Ω 

    3. Reinstall the IGCT No. 2 fuse.

    NG: REPLACE FUSE (IGCT NO. 2 FUSE) 

    OK: Go to Next Step 

  6. INSPECT IGCT RELAY 
    1. Remove the IGCT relay from the engine room relay block.
      Fig 6: Inspecting IGCT Relay
      G04975584Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the IGCT relay resistance.

    Standard resistance 

    TESTER CONNECTION SPECIFIED CONDITION

    Tester Connection Specified Condition
    3-5 10 kΩ or higher
    Below 1 Ω (Apply battery voltage between terminals 1 and 2)

    NG: REPLACE IGCT RELAY 

    OK: Go to Next Step 

  7. CHECK HARNESS AND CONNECTOR (IGCT RELAY- HYBRID VEHICLE CONTROL ECU) 
    1. Remove the IGCT relay from the engine room relay block.
    2. Disconnect the hybrid vehicle control ECU connector.
      Fig 7: Identifying Harness And Connector (IGCT Relay- Hybrid Vehicle Control ECU)
      G05625680Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      1 (IGCT Relay) - A43-12 (MREL) Always Below 1 Ω
    4. Reinstall the IGCT relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (IGCT RELAY- HYBRID VEHICLE CONTROL ECU) 

    OK: Go to Next Step 

  8. CHECK HARNESS AND CONNECTOR 
    1. Remove the IGCT relay from the engine room relay block.
      Fig 8: Identifying IGCT Relay
      G05625681Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance (Check for open) 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified condition
      1 (IGCT relay) - Body ground Always Below 1 Ω
    3. Reinstall the IGCT relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

  9. CHECK FUSE (IGN FUSE) 
    1. Remove the IGN fuse from the instrument panel junction block.
      Fig 9: Identifying IGN Fuse
      G05625682Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Condition Condition Specified Condition
      IGN fuse Always Below 1 Ω
    3. Reinstall the IGN fuse.

    NG: REPLACE FUSE (IGN FUSE) 

  10. CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - IG2 RELAY) 
    1. Remove the IG2 relay from the engine room relay block.
    2. Disconnect the hybrid vehicle control ECU connector.
      Fig 10: Identifying Hybrid Vehicle Control ECU Connector
      G05625683Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      IG2 relay terminal 3 -D35-9 (IGSW) Always Below 1 Ω
    4. Reconnect the ECM connector.
    5. Reinstall the IG2 relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (HYBRID VEHICLE CONTROL ECU - IG2 RELAY) 

    OK: Go to Next Step 

  11. INSPECT IG2 RELAY 
    1. Remove the IG2 relay from the engine room relay block.
      Fig 11: Identifying IG2 Relay Terminals
      G04942983Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      3-5 When no battery voltage applied to terminals 1 and 2 10 kΩ or higher
      When battery voltage applied to terminals 1 and 2 Below 1 Ω
    3. Reinstall the IG2 relay.

    NG: REPLACE IG2 RELAY 

    OK: Go to Next Step 

  12. CHECK FUSE (IG2 FUSE) 
    1. Remove the IG2 fuse from the engine room relay block.
      Fig 12: Identifying IG2 Fuse
      G05625685Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      IG2 fuse Always Below 1 Ω
    3. Reinstall the IG2 fuse

    NG: REPLACE FUSE (IG2 FUSE) 

    OK: Go to Next Step 

  13. CHECK HARNESS AND CONNECTOR (IG2 RELAY POWER SOURCE) 
    1. Remove the IG2 relay from the engine room relay block.
      Fig 13: Identifying IG2 Relay Terminals
      G05413896Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the power switch on (IG)
    3. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Switch Condition Specified Condition
      5 - Body ground Power switch on (IG) 9 to 14 V
    4. Reinstall the IG2 relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (IG2 RELAY - BATTERY) 

    OK: Go to Next Step 

  14. CHECK HARNESS AND CONNECTOR (IG2 RELAY - BODY GROUND) 
    1. Remove the IG2 relay from the engine room relay block.
      Fig 14: Identifying IG2 Relay Terminals
      G05413896Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      2 - Body ground Always Below 1 Ω
    3. Reinstall the IG2 relay.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (IG2 RELAY - BODY GROUND) 

    OK: Go to Next Step 

  15. CHECK HARNESS AND CONNECTOR (ENGINE ROOM RELAY BLOCK - MAIN BODY ECU) 
    1. Remove the IG2 relay from the engine room relay block.
    2. Remove the instrument panel junction block (main body ECU).
      Fig 15: Identifying Harness & Connector (Engine Room No. 1 Relay Block - Main Body ECU)
      G05413901Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance (Check for open) 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      IG2 relay holder terminal (1) - D7-11 (IG2D) Always Below 1 Ω

      Standard resistance (Check for short) 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      D7-11 (IG2D) - Body ground Always 10 kΩ or higher
    4. Reinstall the IG2 relay.
    5. Reconnect the main body ECU connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (ENGINE ROOM RELAY BLOCK - MAIN BODY ECU) 

    OK: CHECK SMART KEY SYSTEM  (See PROBLEM SYMPTOMS TABLE )

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