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MIL Circuit [10/2013 - ]: Procedure

  1. CHECK THAT MIL IS ILLUMINATED 
    1. Check the illumination of the MIL.

      Result

      Condition Proceed to
      MIL remains on A
      MIL remains off (Does not illuminate at all) B
      MIL illuminates and should turn off after power switch on (READY) C

    B → See step   5 

    C → See step   10 

    A: Go to next step 

  2. CHECK WHETHER MIL TURNS OFF 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
    5. Check if any DTCs have been stored. Note down the DTCs.
    6. Clear the DTCs. Refer to DTC CHECK / CLEAR [10/2013 - ] .
    7. Check if the MIL goes off.

      OK

      MIL goes off.

    NG → See step   3 

    OK → See step   8 

  3. CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT IN WIRE HARNESS) 
    1. Disconnect the A57 ECM connector.
      GTY323868Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to ECM)
    2. Turn the power switch on (IG).
    3. Check that the MIL is not illuminated.

      OK

      MIL is not illuminated.

    NG → See step   4 

    OK → See step   9 

  4. CHECK HARNESS AND CONNECTOR (NO. 3 METER CIRCUIT PLATE - ECM) 
    1. Disconnect the No. 3 meter circuit plate 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 Condition Specified Condition
      L27-25 (EFI) or A57-36 (W) - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   12 

  5. CHECK THAT ENGINE STARTS 
    1. Turn the power switch on (IG).
    2. Put the engine in inspection mode (maintenance mode). Refer to INSPECTION MODE PROCEDURE [10/2013 - ] .
    3. Start the engine.

      Result

      Result Proceed to
      Engine starts A
      Engine cannot be put in inspection mode*
      (Engine cannot start)      		 B

      HINT: 

      *: The Techstream cannot communicate with the ECM.

    B → See step   11 

    A: Go to next step 

  6. CHECK HARNESS AND CONNECTOR (ECM TERMINAL VOLTAGE) 
    1. Disconnect the ECM connector.
      GTY290029Courtesy 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 Switch Condition Specified Condition
      A57-36 (W) - Body ground Power switch on (IG) 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to ECM)

    NG → See step   7 

    OK → See step   9 

  7. CHECK HARNESS AND CONNECTOR (NO. 3 METER CIRCUIT PLATE - ECM) 
    1. Disconnect the No. 3 meter circuit plate 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 Condition Specified Condition
      L27-25 (EFI) - A57-36 (W) Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   12 

  8. REPAIR CIRCUITS INDICATED BY OUTPUT DTCS. Refer to  DIAGNOSTIC TROUBLE CODE CHART [10/2013 - ] 
  9. REPLACE ECM. Refer to  REMOVAL [10/2013 - ] 
  10. CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS [10/2013 - ] 
  11. GO TO VC OUTPUT CIRCUIT. Refer to  VC Output Circuit [10/2013 - ]  
  12. REPLACE NO. 3 METER CIRCUIT PLATE. Refer to  DISASSEMBLY [10/2013 - ] 
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