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Home >> Lexus >> 2010 >> SC 430 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P0351-U0101) & Circuit Tests) >> SFI System >> MIL Circuit >> Procedure
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MIL Circuit: Procedure

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

      Result

      Result Proceed to
      MIL remains on A
      MIL is not illuminated B

    B → See step   5 

    A: Go to next step 

  2. CHECK IF MIL TURNS OFF 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON and turn the Techstream on.
    3. Check if DTCs have been stored. Refer to DIAGNOSTIC TROUBLE CODE CHART . If DTCs are present, write them down.
    4. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    5. Check that the MIL turns off.

      OK

      MIL turns off.

    NG → See step   3 

    OK → REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

  3. CHECK HARNESS AND CONNECTOR (FOR SHORT) 
    Fig 1: Identifying E5 ECM Connector
    GTY144283Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E5 ECM connector.
    2. Turn the ignition switch to ON.
    3. Check that the MIL is not illuminated.

      OK

      MIL is not illuminated.

    NG → See step   4 

    OK → See step   11 

  4. CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM) 
    Fig 2: Identifying C8 And E5 Terminal Connectors
    GTY131970Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the C8 combination meter connector.
    2. Disconnect the E5 ECM connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard Resistance

      Tester Connection Specified Condition
      C8-6 (CHK) - E5-8 (W) Below 1 Ω
      C8-6 (CHK) or E5-8 (W) - Body ground 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   9 

  5. CHECK THAT MIL IS ILLUMINATED 
    1. Check that the MIL is illuminated when turning the ignition switch to ON.

      OK

      MIL is illuminated.

    NG → See step   6 

    OK → END 

  6. CHECK THAT ENGINE STARTS 
    1. Turn the ignition switch to ON.
    2. Start the engine.

      Result

      Result Proceed to
      Engine starts A
      Engine does not start* B

      HINT: 

      *: The Techstream cannot communicate with the ECM.

    B → See step   12 

    A: Go to next step 

  7. CHECK HARNESS AND CONNECTOR (COMBINATION METER - BODY GROUND) 
    Fig 3: Identifying E5 ECM Connector
    GTY144283Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E5 ECM connector.
    2. Turn the ignition switch to ON.
    3. Measure the voltage of the wire harness side connectors

      Standard Voltage

      Tester Connection Specified Condition
      E5-8 (W) - Body ground 11 to 14 V

    NG → See step   8 

    OK → See step   13 

  8. CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM) 
    Fig 4: Identifying C8 And E5 Terminal Connectors
    GTY131970Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the C8 combination meter connector.
    2. Disconnect the E5 ECM connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard Resistance

      Tester Connection Specified Condition
      C8-6 (CHK) - E5-8 (W) Below 1 Ω
      C8-6 (CHK) or E5-8 (W) - Body ground 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   10 

  9. REPAIR OR REPLACE COMBINATION METER. Refer to  REMOVAL 
  10. REPAIR OR REPLACE COMBINATION METER. Refer to  REMOVAL 
  11. REPLACE ECM. Refer to  REMOVAL 
  12. GO TO VC OUTPUT CIRCUIT. Refer to  VC Output Circuit  
  13. REPLACE ECM. Refer to  REMOVAL 
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