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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 Techstream 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.
    2. Turn the ignition switch ON.
    3. Check that the MIL is not illuminated.

    OK: 

    MIL is not illuminated. 

    OK: REPLACE ECM 

    Fig 1: Identifying E5 ECM Connector
    G05291564Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to next step 

  4. CHECK WIRE HARNESS (COMBINATION METER - ECM) 
    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 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 

    Fig 2: Checking Wire Harness (Combination Meter - ECM)
    G05291565Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    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 Techstream 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.
    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 

    Fig 3: Identifying E5 ECM Connector
    G05291564Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to next step 

  8. CHECK WIRE HARNESS (COMBINATION METER - ECM) 
    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 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 

    Fig 4: Checking Wire Harness (Combination Meter - ECM)
    G05291565Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPAIR OR REPLACE COMBINATION METER 

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