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Home >> Lexus >> 2008 >> IS 250 AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (4GR-FSE) - System And Component Testing, On-Vehicle Inspection, Removal, Inspection & Installation >> MIL Circuit >> Inspection Procedure
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Inspection Procedure

HINT:

Troubleshoot each problem symptom in accordance with the chart below.

PROCEDURE CHART

MIL remains illuminated Start inspection from step 1
MIL not illuminated Start inspection from step 4
  1. CHECK WHETHER MIL TURN OFF 
    1. Connect Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the tester on.
    4. Check whether any DTCs have been stored (See DTC CHECK/CLEAR ). Note them down if necessary.
    5. Clear DTCs (See DTC CHECK/CLEAR ).
    6. Check if the MIL turns off.

    OK: MIL turns off. 

    OK: REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

    NG: Go to Next Step 

  2. CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT IN WIRE HARNESS) 
    1. Disconnect the A6 ECM connector.
    2. Turn the engine switch on (IG).
    3. Check the MIL is not illuminated.

      OK: MIL is not illuminated. 

    4. Reconnect the ECM connector.
      5. Fig 1: Identifying A6 ECM Connector
      G05316189Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE ECM 

    NG: Go to Next Step 

  3. CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM) 
    1. Disconnect the A6 ECM connector.
    2. Disconnect the J35 combination meter connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance (Check for open) 

      RESISTANCE SPECIFICATION CHART

      Tester Connection Specified Condition
      W (A6-8) - EFI (J35-12) Below 1 Ω

      Standard resistance (Check for short) 

      RESISTANCE SPECIFICATION CHART

      Tester Connection Specified Condition
      W (A6-8) or EFI (J35-12) - Body ground 10 kΩ or higher
    4. Reconnect the connectors.
      5. Fig 2: Identifying J35 Combination Meter Connector And A6 ECM Connector
      G05823300Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPAIR OR REPLACE COMBINATION METER ASSEMBLY 

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

    OK: MIL is illuminated. 

    OK: END 

    NG: Go to Next Step 

  5. CHECK HARNESS AND CONNECTOR 
    1. Disconnect the A6 ECM connector.
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFICATION CHART

      Tester Connection Specified Condition
      W (A6-8) - Body ground 10 to 14 V
    4. Reconnect the ECM connector.
      5. Fig 3: Identifying A6 ECM Connector
      G05316189Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE ECM 

    NG: Go to Next Step 

  6. CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM) 
    1. Disconnect the A6 ECM connector.
    2. Disconnect the J35 combination meter connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard resistance (Check for open) 

      RESISTANCE SPECIFICATION CHART

      Tester Connection Specified Condition
      W (A6-8) - EFI (J35-12) Below 1 Ω

      Standard resistance (Check for short) 

      RESISTANCE SPECIFICATION CHART

      Tester Connection Specified Condition
      W (A6-8) or EFI (J35-12) - Body ground 10 kΩ or higher
    4. Reconnect the connectors.
      5. Fig 4: Identifying J35 Combination Meter Connector And A6 ECM Connector
      G05823300Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPAIR OR REPLACE COMBINATION METER ASSEMBLY 

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

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