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Inspection Procedure

  1. CHECK THAT MIL IS ILLUMINATED 
    1. Turn the engine switch on (IG)
    2. Check the illumination of the MIL

      Result 

      RESULT CHART

      Result Proceed to
      MIL remains illuminated (Even after engine switch on (IG) and several seconds have passed, MIL still remains illuminated) A
      MIL remains off (Does not illuminate at all) B
      MIL illuminates for several seconds, but turns off after engine is started C

    B: Go to step  5

    C: SYSTEM OK 

    A: Go to next step 

  2. CHECK IF MIL TURNS OFF 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG) and turn the Techstream ON.
    3. Check if DTCs have been stored (See DTC CHECK/CLEAR ) If DTCs are present, write them down.
    4. Clear DTCs (See DTC CHECK/CLEAR ).
    5. Check that the MIL turns off.

      OK: MIL turns off. 

    NG: Go to step 3 

    OK: REPAIR CIRCUITS INDICATED BY OUTPUT DTCS  (See DIAGNOSTIC TROUBLE CODE CHART )

  3. CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT IN WIRE HARNESS) 
    1. Disconnect the ECM connector
    2. Turn the engine switch on (IG).
    3. Check that the MIL is not illuminated.

      OK: MIL is not illuminated. 

    4. Reconnect the ECM connector.
      5. Fig 1: Identifying ECM Connector A5
      G05751840Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step 4 

    OK: REPLACE ECM  (See REMOVAL  )

  4. CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM) 
    1. Disconnect the combination meter connector.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below

      Standard Resistance (Check for Short) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      J35-12 (EFI) or A5-11 (W) - Body ground Always 10 kΩ or higher
    4. Reconnect the combination meter connector and ECM connector.
      5. Fig 2: Identifying Combination Meter Connector J35 And ECM Connector A5
      G05751841Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPAIR OR REPLACE COMBINATION METER  (See REMOVAL )

  5. CHECK THAT ENGINE STARTS 
    1. Start the engine

      Result 

      RESULT CHART

      Result Proceed to
      Engine starts A
      Engine does not start* B
      HINT.
      *: The tester cannot communicate with the ECM.

    B: GO TO VC OUTPUT CIRCUIT 

    A: Go to next step 

  6. CHECK HARNESS AND CONNECTOR (ECM TERMINAL VOLTAGE) 
    1. Disconnect the ECM connector.
    2. Turn the engine 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
      A5-11 (W) - Body ground Engine switch on (IG) 11 to 14 V
    4. Reconnect the ECM connector
      5. Fig 3: Identifying ECM Connector A5
      G05751842Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step 7 

    OK: REPLACE ECM  (See REMOVAL  )

  7. CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM) 
    1. Disconnect the combination meter connector.
    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
      J35-12 (EFI) - A5-11 (W) Always Below 1 Ω
    4. Reconnect the combination meter connector and ECM connector
      5. Fig 4: Identifying Combination Meter Connector J35 And ECM Connector A5
      G05751843Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE COMBINATION METER ASSEMBLY  (See REMOVAL )

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