2008 Lexus IS 350FACTORY OEM SERVICE PROCEDURE

How To Proceed With Troubleshooting

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.

HINT

  • Use the following procedure to troubleshoot the LIN communication system.
  • *: Use the Techstream
  1. VEHICLE BROUGHT TO WORKSHOP 
  2. CUSTOMER PROBLEM ANALYSIS 

    HINT.

    • In troubleshooting, confirm that the problem symptoms have been accurately identified. Preconceptions should be discarded in order to make an accurate judgment To clearly understand what the problem symptoms are, it is extremely important to ask the customer about the problem and the conditions at the time the malfunction occurred.
    • Gather as much information as possible for reference. Past problems that seem unrelated may also help in some cases.
    • The following 5 items are important points in the problem analysis.
    REFERENCE CHART

    What Vehicle, system name
    When Date, time, occurrence frequency
    Where Road conditions
    Under what conditions? Driving conditions, weather conditions
    How did it happen? Problem symptoms
  3. INSPECT BATTERY VOLTAGE 
    1. Measure the battery voltage

      Standard Voltage: 

      11 to 14 V 

      If the voltage is below 11V, recharge or replace the battery before proceeding.

  4. INSPECT COMMUNICATION FUNCTION OF LIN COMMUNICATION SYSTEM* 
    1. Using the Techstream, inspect the LIN communication function to ensure there are no malfunctions in the communication system (See DIAGNOSIS SYSTEM  )

      Result 

      DTC RESULT REFERENCE

      Result Proceed to
      No DTCs output A
      DTCs output B

    B: GO TO DIAGNOSTIC TROUBLE CODE CHART 

    A: Go to Next Step 

  5. OVERALL ANALYSIS AND TROUBLESHOOTING* 
    1. Terminals of ECU (See TERMINALS OF ECU  )
  6. REPAIR OR REPLACE 
  7. CONFIRMATION TEST 

    NEXT: END 

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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.