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Inspection Procedure

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

      Result 

      RESULT CHART

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

    B: Go to step  5

    A: Go to next step 

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

      OK: 

      MIL turns off. 

    OK: REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

    NG: Go to next step 

  3. CHECK WIRE HARNESS (FOR SHORT) 
    1. Disconnect the E5 ECM connector.
      Fig 1: Disconnecting E5 ECM Connector Terminals
      G05291564Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the ignition switch ON.
    3. Check that the MIL is not illuminated.

      OK: 

      MIL is not illuminated. 

    OK: REPLACE ECM 

    NG: Go to next step 

  4. CHECK WIRE HARNESS (COMBINATION METER - ECM) 
    1. Disconnect the C8 combination meter connector.
      Fig 2: Identifying C8 Combination Meter Connector Terminals
      G05291565Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the E5 ECM connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      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 AND CONNECTOR 

    OK: REPAIR OR REPLACE COMBINATION METER 

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

      OK: 

      MIL is illuminated. 

    OK: SYSTEM OK 

    NG: Go to next step 

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

      Result 

      RESULT CHART

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

    B: GO TO VC OUTPUT CIRCUIT 

    A: Go to next step 

  7. CHECK WIRE HARNESS (COMBINATION METER - BODY GROUND) 
    1. Disconnect the E5 ECM connector.
      Fig 3: Disconnecting E5 ECM Connector Terminals
      G05291566Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Turn the ignition switch ON.
    3. Measure the voltage of the wire harness side connectors

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      E5-8 (W) - Body ground 10 to 14 V

    OK: REPLACE ECM 

    NG: Go to next step 

  8. CHECK WIRE HARNESS (COMBINATION METER - ECM) 
    1. Disconnect the C8 combination meter connector.
      Fig 4: Identifying C8 Combination Meter Connector Terminals
      G05291567Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the E5 ECM connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      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 AND CONNECTOR 

    OK: REPAIR OR REPLACE COMBINATION METER 

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