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Home >> Toyota >> 2009 >> Highlander Base, 3.5 S, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (2GR-FE) - System And Component Testing, Removal, Inspection And Installation >> ECM Power Source Circuit >> Inspection Procedure
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Inspection Procedure

  1. INSPECT ECM (+B VOLTAGE) 
    1. Turn the ignition switch on (IG).
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      D35-1 (+B) - B3-1 (E1) Ignition switch on (IG) 9 to 14 V
      D35-2 (+B2) - B3-1 (E1) Ignition switch on (IG) 9 to 14 V

      NG: Go to step 2 

      Fig 1: Identifying ECM B3 And D35 Connector Terminals
      G05413887Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

  2. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the ECM 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 Condition Specified Condition
      B3-1 (E1) - Body ground Always Below 1 Ω
    3. Reconnect the ECM connector.

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

      Fig 2: Identifying ECM B3 Connector Terminals
      G05413888Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  3. INSPECT ECM (MREL VOLTAGE) 
    1. Turn the ignition switch on (IG).
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      D35-8 (MREL) - B3-1 (E1) Ignition switch on (IG) 9 to 14 V

      NG: Go to step  8

      Fig 3: Identifying ECM B3 And D35 Connector Terminals
      G05413889Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  4. CHECK FUSE (EFI MAIN AND EFI NO. 2 FUSE) 
    1. Remove the EFI MAIN and EFI No. 2 fuse from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      EFI MAIN fuse Always Below 1 Ω
      EFI No. 2 fuse Always Below 1 Ω
    3. Reinstall the fuses.

      NG: REPLACE FUSE (EFI MAIN OR EFI NO. 2 FUSE) 

      Fig 4: Identifying EFI Main And EFI No. 2 Fuse
      G05413890Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  5. INSPECT ENGINE ROOM JUNCTION BLOCK ASSEMBLY (EFI RELAY) 
    1. Inspect the EFI relay (See INSPECTION  ).

      NG: REPLACE ENGINE ROOM JUNCTION BLOCK  (See REMOVAL  )

      OK: Go to next step 

  6. CHECK HARNESS AND CONNECTOR (EFI RELAY - ECM, EFI RELAY - BODY GROUND) 
    1. Remove the engine room junction block from the engine room relay block.
    2. Disconnect the ECM 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 Condition Specified Condition
      2E-9 (EFI relay terminal) - D35-8 (MREL) Always Below 1 Ω
      2E-10 (EFI relay terminal) - Body ground Always Below 1 Ω

      Check for short 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      2E-9 (EFI relay terminal) or D35-8 (MREL) - Body ground Always 10 kΩ or higher
    4. Reinstall the engine room junction block.
    5. Reconnect the ECM connector.

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI RELAY - ECM) 

      Fig 5: Identifying Engine Room Junction Block And ECM MREL Connector Terminals
      G05413891Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (EFI RELAY - ECM) 
    1. Remove the engine room junction block from the engine room relay block.
    2. Disconnect the ECM 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 Condition Specified Condition
      2E-6 (EFI relay terminal) - D35-1 (+B) Always Below 1 Ω
      2E-6 (EFI relay terminal) - D35-2 (+B2) Always Below 1 Ω

      Check for short 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      2E-6 (EFI relay terminal) or D35-1 (+B) - Body ground Always 10 kΩ or higher
      2E-6 (EFI relay terminal) or D35-2 (+B2) - Body ground Always 10 kΩ or higher
    4. Reinstall the engine room junction block assembly.
    5. Reconnect the ECM connector.

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI RELAY - ECM) 

      Fig 6: Identifying Engine Room Junction Block And ECM +B2, +B Connector Terminals
      G05413892Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI RELAY - EFI MAIN FUSE) 

  8. INSPECT ECM (IGSW VOLTAGE) 
    1. Turn the ignition switch on (IG).
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      D35-9 (IGSW) - B3-1 (E1) Ignition switch on (IG) 9 to 14 V

      NG: Go to step 9 

      Fig 7: Identifying ECM B3 And D35 Connector Terminals
      G05413893Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: REPLACE ECM  (See REMOVAL  )

  9. CHECK HARNESS AND CONNECTOR (ECM - IG2 RELAY) 
    1. Remove the IG2 relay from the engine room relay block.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      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: Go to step  13

      Fig 8: Identifying Engine Room Relay Block And ECM Connector Terminals
      G05413894Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  10. INSPECT IG2 RELAY 
    1. Remove the IG2 relay from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 9: IG2 Relay Circuit
      G04942983Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      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 

  11. CHECK HARNESS AND CONNECTOR (IG2 RELAY POWER SOURCE) 
    1. Remove the IG2 relay from the engine room relay block.
    2. Turn the ignition switch on (IG)
    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

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

      NG: Go to step  14

      Fig 10: Identifying IG2 Relay
      G05413896Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  12. CHECK HARNESS AND CONNECTOR (IG2 RELAY - BODY GROUND) 
    1. Remove the IG2 relay from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

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

      Result 

      RESULT CHART

      Result Proceed to
      NG A
      OK (w/o Smart Key System) B
      OK (w/ Smart Key System) C
      Fig 11: Identifying IG2 Relay
      G05413896Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      B: Go to step  15

      C: Go to step  17

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

  13. CHECK FUSE (IG2 FUSE) 
    1. Remove the IG2 fuse from the engine room relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

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

      NG: REPLACE FUSE (IG2 FUSE) 

      Fig 12: Identifying IG2 Fuse
      G05413898Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

  14. CHECK FUSE (IGN FUSE) 
    1. Remove the IGN fuse from the instrument panel junction block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

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

      NG: REPLACE FUSE (IGN FUSE) 

      Fig 13: Identifying IGN Fuse
      G05413899Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (IG2 RELAY - ECM) 

  15. CHECK HARNESS AND CONNECTOR (IGNITION SWITCH - IG2 RELAY) 
    1. Remove the IG2 relay from the engine room relay block.
    2. Disconnect the ignition switch 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 Condition Specified Condition
      D24-6 (IG2) - IG2 relay terminal 1 Always Below 1 Ω

      Check for short 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      D24-6 (IG2) or IG2 relay terminal 1 - Body ground Always 10 kΩ or higher
    4. Reinstall the IG2 relay.
    5. Reconnect the ignition switch connector.

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

      Fig 14: Identifying IG2 Relay And Ignition Switch Connector Terminals
      G05413900Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  16. INSPECT IGNITION SWITCH 
    1. Inspect the ignition switch assembly (See INSPECTION ).

      NG: REPLACE IGNITION SWITCH  (See IGNITION SWITCH )

      OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (IGNITION SWITCH - BATTERY) 

  17. 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).
    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 Condition Specified Condition
      IG2 relay holder terminal (1) - D7-11 (IG2D) Always Below 1 Ω
      IG2 relay holder terminal (2) - Body ground Always Below 1 Ω

      Standard resistance (Check for short) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      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: CHECK SMART KEY SYSTEM  (See HOW TO PROCEED WITH TROUBLESHOOTING )

      Fig 15: Identifying IG2 Relay Main Body ECU Connector Terminals
      G05413901Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 

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