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Home >> Toyota >> 2009 >> Highlander Base, 2.7 A >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (1AR-FE) - Circuit Testing, Component Inspection, Removal & Installation >> ECM Power Source Circuit >> Inspection Procedure
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Inspection Procedure

NOTE: Inspect the fuses for circuits related to this system before performing the following inspection procedure.
  1. INSPECT ECM (+B VOLTAGE) 
    1. Turn the ignition switch to ON.
    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
      D61-23 (+B) - B49-6 (E1) Ignition switch ON 11 to 14 V
      D61-24 (+B2) - B49-6 (E1) Ignition switch ON 11 to 14 V

      NG: Go to step 2 

      Fig 1: Identifying ECM Connector Terminals
      G06111212Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE  (See TERMINALS OF ECM )

  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
      B49-6 (E1) - Body ground Always Below 1 Ω
    3. Reconnect the ECM connector.

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      Fig 2: Disconnecting ECM B49 Connector
      G06111213Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  3. INSPECT ECM (MREL VOLTAGE) 
    1. Turn the ignition switch to ON.
    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
      D60-36 (MREL) - B49-6 (E1) Ignition switch ON 11 to 14 V

      NG: Go to step  8

      Fig 3: Identifying ECM Connector Terminals
      G06111214Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

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

      NG: REPLACE ENGINE ROOM JUNCTION BLOCK ASSEMBLY 

      OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (EFI RELAY - ECM) 
    1. Remove the engine room junction block assembly 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 - D60-36 (MREL) Always Below 1 Ω

      Standard Resistance (Check for Short) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      2E-9 or D60-36 (MREL) - 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 

      Fig 4: Identifying Engine Room Junction Block Assembly And ECM Connector
      G06111215Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  6. CHECK HARNESS AND CONNECTOR (EFI RELAY - BODY GROUND) 
    1. Remove the engine room junction block assembly from the engine room relay block.
    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
      2E-10 - Body ground Always Below 1 Ω
    3. Reinstall the engine room junction block assembly.

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      Fig 5: Identifying Engine Room Junction Block Assembly
      G06111216Courtesy 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 assembly 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 - D61-23 (+B) Always Below 1 Ω
      2E-6 - D61-24 (+B2) Always Below 1 Ω

      Standard Resistance (Check for Short) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      2E-6 or D61-23 (+B) - Body ground Always 10 kΩ or higher
      2E-6 or D61-24 (+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 

      Fig 6: Identifying Engine Room Junction Block Assembly And ECM Connector
      G06111217Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

  8. INSPECT ECM (IG SW VOLTAGE) 
    1. Turn the ignition switch to ON.
    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
      D60-21 (IG SW) - B49-6 (E1) Ignition switch ON 11 to 14 V

      NG: Go to step 9 

      Fig 7: Identifying ECM Connector Terminals
      G06111218Courtesy 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 -D60-21 (IG SW) Always Below 1 Ω
    4. Reconnect the ECM connector.
    5. Reinstall the IG2 relay.

      NG: Go to step  13

      Fig 8: Identifying IG2 Relay And ECM Connector
      G06111219Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  10. INSPECT RELAY (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.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      3 - 5 Battery voltage is not applied between terminals 1 and 2 10 kΩ or higher
      Battery voltage applied between terminals 1 and 2 Below 1 Ω
      Fig 9: IG2 Relay Circuit Diagram
      G04942983Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reinstall the IG2 relay.

      NG: REPLACE RELAY (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. Measure the voltage according to the value (s) in the table below.

      Standard Voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      IG2 relay terminal 5 - Body ground Always 11 to 14 V
    3. Reinstall the IG2 relay.

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

      Fig 10: Identifying IG2 Relay Location
      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
      IG2 relay terminal 2 - Body ground Always Below 1 Ω
    3. Reinstall the IG2 relay.

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      Fig 11: Identifying IG2 Relay Location
      G05413896Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  13. CHECK HARNESS AND CONNECTOR (IGNITION SWITCH ASSEMBLY - IG2 RELAY) 
    1. Remove the IG2 relay from the engine room relay block.
    2. Disconnect the ignition switch assembly 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

      Standard Resistance (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 assembly connector.

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      Fig 12: Identifying IG2 Relay And Ignition Switch Assembly Connector
      G06111223Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

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

      NG: REPLACE IGNITION SWITCH ASSEMBLY  (See REMOVAL )

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

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