2004 Lexus SC 430FACTORY OEM SERVICE PROCEDURE

How To Proceed With Troubleshooting

  1. VEHICLE BROUGHT TO WORKSHOP 
  2. CUSTOMER PROBLEM ANALYSIS (See  CUSTOMER PROBLEM ANALYSIS CHECK   ) 
  3. CONNECT OBD HAND-HELD TESTER TO DLC3 

    HINT:

    If the display indicates a communication fault in the tool, inspect the DLC3.

  4. CHECK DTC AND FREEZE FRAME DATA (See  DTC CHECK/CLEAR   ) 

    HINT:

    Record or print DTC and freeze frame data, if needed.

  5. CLEAR DTC AND FREEZE FRAME DATA (See  DTC CHECK/CLEAR   ) 
  6. VISUAL INSPECTION 
  7. SETTING CHECK (TEST) MODE DIAGNOSIS (See  CHECK MODE PROCEDURE   ) 
  8. PROBLEM SYMPTOM CONFIRMATION 

    HINT:

    If the engine does not start, perform steps 10 and 12 first.

    Fig 1: Problem Symptom Confirmation Chart
    G01447291Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. B: Go to step   10 
    2. A: Go to next step. 
  9. SYMPTOM SIMULATION 
  10. DTC CHECK (See  DTC CHECK/CLEAR   ) 
    Fig 2: DTC Malfunction Code
    G01447292Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. B: Go to step   12 
    2. A: Go to next step. 
  11. DTC CHART (See  DIAGNOSTIC TROUBLE CODE CHART   ) 

    Go to step   14 

  12. BASIC INSPECTION (See  BASIC INSPECTION   ) 
    Fig 3: Basic Inspection Chart
    G01447293Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. B: Go to step   17 
    2. A: Go to next step. 
  13. PROBLEM SYMPTOMS TABLE (See  PROBLEM SYMPTOMS TABLE   ) 
    Fig 4: Problem Symptoms Table
    G01447294Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. B: Go to step   17 
    2. A: Go to next step. 
  14. CHECK ECM POWER SOURCE CIRCUIT (See  ECM POWER SOURCE CIRCUIT   ) 
  15. CIRCUIT INSPECTION 
    Fig 5: Circuit Inspection Chart
    G01447295Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. B: Go to step   18 
    2. A: Go to next step. 
  16. CHECK FOR INTERMITTENT PROBLEMS (See  CHECK FOR INTERMITTENT PROBLEMS   ) 

    Go to step   18 

  17. PARTS INSPECTION 
  18. IDENTIFICATION OF PROBLEM 
  19. ADJUSTMENT, REPAIR 
  20. CONFIRMATION TEST 

    21. END 

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.