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Inspection Procedure

  1. CHECK THAT MIL IS ILLUMINATED 
    1. Perform troubleshooting in accordance with the table below:

      Result 

      RESULT CHART

      Conditions Proceed to
      MIL remains ON A
      MIL does not illuminate B

    B:  Go to step  5

    A: Go to step 

  2. CHECK WHETHER MIL TURNS OFF 
    1. Connect Techstream to the DLC3.
    2. Turn the engine switch on (IG) and turn the tester on.
    3. Select the following menu items: Powertrain / Engine / Trouble Code.
    4. Check if any DTCs have been stored. Note down any DTCs.
    5. Clear the DTCs (See DTC CHECK/CLEAR ).
    6. Check if the MIL goes off.

      Standard: 

      MIL goes off. 

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

    NG: Go to next step. 

  3. CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT IN WIRE HARNESS) 
    1. Disconnect the A10 ECM connector.
    2. Turn the engine switch on (IG).
    3. Check that the MIL is not illuminated.
      Fig 1: Identifying Terminals Of A10 ECM Connector
      G05247886Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: 

      MIL is not illuminated. 

    4. Reconnect the ECM connector.

    OK: REPLACE ECM (See  REMOVAL   ) 

    NG: Go to next step. 

  4. CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM) 
    1. Disconnect the A10 ECM connector.
    2. Disconnect the E20 combination meter connector.
    3. Measure the resistance.

      Standard Resistance (Check for short) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      A10-24 (W) or E20-4 (CHK) - Body ground 10 kΩ or higher
      Fig 2: Identifying Terminals Of A10 ECM And E20 Combination Meter Connectors
      G05247887Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Reconnect the ECM connector.
    5. Reconnect the combination meter connector.

    OK: REPAIR OR REPLACE COMBINATION METER ASSEMBLY 

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

  5. CHECK THAT MIL IS ILLUMINATED 
    1. Check if the MIL is illuminated when the engine switch is turned on (IG).

      OK: 

      MIL is illuminated. 

    OK: SYSTEM OK 

    NG: Go to next step. 

  6. CHECK THAT ENGINE STARTS 
    1. Turn the engine switch on (IG).
    2. Start the engine.

      Result 

      RESULT CHART

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

    B:  GO TO VC OUTPUT CIRCUIT 

    A: Go to next step. 

  7. INSPECT COMBINATION METER ASSEMBLY (MIL CIRCUIT) 
    1. Check the MIL circuit (See HOW TO PROCEED WITH TROUBLESHOOTING ).

    NG: REPAIR OR REPLACE COMBINATION METER ASSEMBLY 

    OK: CHECK AND REPLACE HARNESS AND CONNECTOR (COMBINATION METER - ECM) 

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