2012 Lexus IS 250C Automatic TransFACTORY OEM SERVICE PROCEDURE

Confirmation Driving Pattern

NOTE:
  • The Evaporative System Check (Automatic Mode) consists of 6 steps performed automatically by the Techstream. It takes a maximum of approximately 18 minutes.
  • Do not perform the Evaporative System Check when the fuel tank is more than 90% full because the cut-off valve may be closed, making the fuel tank leak check unavailable.
  • Do not run the engine during this operation.
  • When the temperature of the fuel is 35°C (95°F) or higher, a large amount of vapor forms and any check results become inaccurate. When performing the Evaporative System Check, keep the fuel temperature below 35°C (95°F).
  1. Connect the Techstream to the DLC3.
  2. Turn the engine switch on (IG) and turn the Techstream on.
  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  4. Turn the engine switch off and wait for at least 30 seconds.
  5. Turn the engine switch on (IG) and turn the Techstream on.
  6. Enter the following menus: Powertrain / Engine / Utility / Evaporative System Check / Automatic Mode.
  7. After the Evaporative System Check is completed, check for All Readiness by entering the following menus: Powertrain / Engine / Utility / All Readiness.
  8. Input the DTC: P2420.
  9. Check the DTC judgment result.
    Techstream Display Description
    NORMAL
    • DTC judgment completed
    • System normal
    ABNORMAL
    • DTC judgment completed
    • System abnormal
    INCOMPLETE
    • DTC judgment not completed
    • Perform driving pattern after confirming DTC enabling conditions
    N/A
    • Unable to perform DTC judgment
    • Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

    HINT: 

    • If the judgment result shows NORMAL, the system is normal.
    • If the judgment result shows ABNORMAL, the system has a malfunction.
  10. If the judgment result is INCOMPLETE or N/A and no pending DTC is output, perform a universal trip and check for permanent DTCs. Refer to DTC CHECK / CLEAR .

    HINT: 

    • If a permanent DTC is output, the system is malfunctioning.
    • If no permanent DTC is output, the system is normal.
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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