How To Proceed With Troubleshooting

2010 Lexus RX 450h 3.5 BSECTION How To Proceed With Troubleshooting

HINT: 

  • Use the following procedure to troubleshoot the power window control system.
  • *: Use the Techstream.
  1. VEHICLE BROUGHT TO WORKSHOP 

    NEXT: Go to next step 

  2. CUSTOMER PROBLEM ANALYSIS 
    • 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:
      What Vehicle model, system name
      When Date, time, occurrence frequency
      Where Road conditions
      Under what conditions? Driving conditions, weather conditions
      How did it happen? Problem symptoms

    NEXT: Go to next step 

  3. PRE-CHECK 
    1. Measure the battery voltage with the power switch off.

      Standard Voltage

      11 to 14 V

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

    2. Check the fuses and relays.
    3. Check the connector connections and terminals to make sure that there are no abnormalities such as loose connections, deformation, etc.

      NEXT: Go to next step 

  4. INSPECT COMMUNICATION FUNCTION OF CAN COMMUNICATION SYSTEM* 
    1. Use the Techstream to check if the CAN communication system is functioning normally.

      Result

      Result Proceed to
      ECU connected, communication line is functioning normally A
      ECU connected, communication line is malfunctioning B

      B → GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 

      A: Go to next step 

  5. INSPECT COMMUNICATION FUNCTION OF LIN COMMUNICATION SYSTEM* 
    1. Use the Techstream to check if the LIN communication system is functioning normally. Refer to DTC CHECK / CLEAR .

      Result

      Result Proceed to
      No DTCs output A
      DTCs output B

      B → GO TO LIN COMMUNICATION SYSTEM. Refer to  DIAGNOSTIC TROUBLE CODE CHART 

      A: Go to next step 

  6. CHECK FOR DTC* 
    1. Check for DTCs and note any codes that are output. Refer to DTC CHECK / CLEAR .
    2. Clear the DTCs.
    3. Recheck for DTCs.

      Result

      Result Proceed to
      No DTCs output A
      DTCs output B

      B → GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART  

      A: Go to next step 

  7. PROBLEM SYMPTOMS TABLE 
    1. Refer to Problem Symptoms Table. Refer to PROBLEM SYMPTOMS TABLE .

      Result

      Result Proceed to
      Fault is not listed in problem symptoms table A
      Fault is listed in problem symptoms table B

      B → Go to step   9 . 

      A: Go to next step 

  8. OVERALL ANALYSIS AND TROUBLESHOOTING* 
    1. Operation Check. Refer to OPERATION CHECK 
    2. Data List / Active Test. Refer to DATA LIST / ACTIVE TEST 
    3. Terminal Connector Identification. Refer to TERMINAL CONNECTOR IDENTIFICATION 

      NEXT: Go to next step 

  9. ADJUST, REPAIR OR REPLACE 
    1. Check if any of the door window regulators or power window regulator motor assemblies have been removed and reinstalled.

      Result

      Result Proceed to
      Any of the door window regulators or power window regulator motor assemblies have been removed and reinstalled. A
      None of the door window regulators or power window regulator motor assemblies has been removed and reinstalled. B

      B → Go to step   11 . 

      A: Go to next step 

  10. INITIALIZE POWER WINDOW REGULATOR MOTOR 
    1. If any of the door window regulators or power window regulator motor assemblies have been removed and reinstalled, perform "Initialize Power Window Control System" (initialization of the pulse sensor) for the applicable door glass. Refer to INITIALIZATION .

      HINT: 

      If "Initialize Power Window Control System" (initialization of the pulse sensor) has not been performed, the auto operation function, jam protection function, key-linked operation function, wireless transmitter-linked operation function and key-off operation function will not operate or will operate incorrectly.

      NEXT: Go to next step 

  11. CONFIRMATION TEST 

    NEXT → END 

RENDER: 1.0x

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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.