2008 Lexus RX 400h FWDFACTORY OEM SERVICE PROCEDURE

SFI System: Initialization

  1. PERFORM INITIALIZATION 
    1. Apply the parking brake and chock the wheels.
    2. Connect Techstream to the DLC3.
    3. Put the engine in the inspection mode (See CHECK MODE PROCEDURE  ).
    4. Select the following menu items: Powertrain / Engine and ECT / Data List / Coolant Temp.
    5. Warm up the engine with the A/C switch off until the engine coolant temperature becomes 83°C (181°F) or more.
    6. Select the following menu items: Powertrain / Hybrid Control / Data List / State of Change.
    7. Move the shift lever to the N position, set the A/C switch to MAX cool or turn on the front defroster, and leave the vehicle until the State of Change value is below 40%.

      HINT:

      If the State of Change is substantially below 40%, the auxiliary battery may go dead. Therefore, do not allow the SOC to reach substantially below 40%.

    8. Move the shift lever to the P position and turn the ignition switch off.
    9. Disconnect the negative terminal from the auxiliary battery and leave it for 1 minute or more.
    10. Reconnect the negative terminal to the auxiliary battery and turn the ignition switch to the ON position.
    11. Select the following menu items: Powertrain / Engine and ECT / Data List / Coolant Temp.
    12. Check that the engine coolant temperature is 83°C (181°F) or more.

      HINT:

      If the engine coolant temperature is below 83°C (181°F), start the engine by depressing the accelerator pedal with the shift lever in the P position to increase the engine coolant temperature.

    13. Select the following menu items: Powertrain / Engine and ECT / Data List / Calculate Load.
    14. Move the shift lever to the D position while depressing the brake pedal with the left foot.
    15. Depress the accelerator pedal with the right foot while firmly depressing the brake pedal with the left foot, and maintain an engine load value of 45% or more (60 to 70% of full acceleration) for approximately 30 seconds.
      NOTE: Do not perform this step for 40 seconds or more.
    16. Shift the shift lever to the P position. Turn the ignition switch off and then wait for 5 seconds before putting the vehicle into the READY-on state again.
    17. Select the following menu items: Powertrain / Engine and ECT / Data List / ISC Leaning.
    18. Check that the air conditioner is off. Lightly depress the accelerator pedal and release it when the engine starts.
    19. Check that Complete is displayed on Techstream screen.

      HINT:

      • If ISC Leaning is not completed within 1 minute, repeat steps ( o) through ( r).
      • The engine will usually stop when ISC Leaning is completed. However, the engine will not stop even when ISC Leaning is completed in such cases when the charge level of the auxiliary battery is decreased.
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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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