2009 Scion tC AutomaticFACTORY OEM SERVICE PROCEDURE

Inspection Procedure

  1. CHECK MIL 
    1. Check that MIL (Malfunction Indicator Lamp) lights up when turning the ignition switch to the ON position.

      Standard: 

      MIL lights up 

      OK: SYSTEM OK 

      NG: Go to Next Step 

  2. CHECK CONNECTION BETWEEN TECHSTREAM AND ECM 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to the ON position and turn the Techstream on.
    3. Check the communication between the Techstream and ECM.

      Result 

      RESULT CHART

      Condition Proceed to
      Communication is possible A
      Communication is not possible B

    A: GO TO MIL CIRCUIT (See  MIL CIRCUIT   )) 

    B: Go to Next Step 

  3. INSPECT ECM (VC VOLTAGE) 
    1. Turn the ignition switch to the ON position.
    2. Measure the voltage according to the value (s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      E8-18 (VC) - E8-3 (E1) Voltage is not 5 V
    Fig 1: Inspecting ECM (VC Voltage)
    G06276460Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. CHECK MIL (THROTTLE POSITION SENSOR) 
    1. Disconnect the T1 throttle body connector.
    2. Turn the ignition switch to the ON position.
    3. Check the MIL.

      Result 

      RESULT CHART

      Condition Proceed to
      MIL illuminates A
      MIL does not illuminate B
    4. Reconnect the throttle body connector.

    A: REPLACE THROTTLE BODY  (See ON-VEHICLE INSPECTION )

    B: Go to Next Step 

  5. CHECK MIL (CANISTER PUMP MODULE) 
    1. Disconnect the T1 throttle body connector.
    2. Turn the ignition switch to the ON position.
    3. Check the MIL

      Result 

      RESULT CHART

      Condition Proceed to
      MIL illuminates A
      MIL does not illuminate B
    4. Reconnect the throttle body connector.

    A: REPLACE CANISTER  (See REMOVAL )

    B: Go to Next Step 

  6. CHECK WIRE HARNESS (ECM - BODY GROUND) 
    1. Disconnect the T1 throttle body connector.
    2. Disconnect the L1 canister pump module connector.
    3. Disconnect the E8 ECM connector.
    4. Measure the resistance according to the value (s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Specified Condition
      E8-18 (VC) - Body ground 10 kΩ or higher
    5. Reconnect the throttle body connector.
    6. Reconnect the canister pump module connector.
    7. Reconnect the ECM connector.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE ECM  (See REMOVAL )

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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