2003 Lexus LS 430FACTORY OEM SERVICE PROCEDURE

General Information: Notes

WARNING: This page is about a different car, the 2005 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.

A large number of ECU controlled systems are used in the 4RUNNER. In general, ECU controlled systems are considered to be very intricate, requiring a high level of technical knowledge to troubleshoot. However, most problem checking procedures only involve inspecting the ECU controlled system's circuits one by one.

An adequate understanding of the system and a basic knowledge of electricity is enough to perform effective troubleshooting, accurate diagnoses and necessary repairs. Detailed information and troubleshooting procedures on major ECU controlled systems in this vehicle are outlined below:

TROUBLESHOOTING REFERENCE

System Example
1. SFI System (1GR-FE) SFI SYSTEM (1GR-FE)
2. SFI System (2UZ-FE) SFI SYSTEM (2UZ-FE)
3. Tire Pressure Warning System TIRE PRESSURE WARNING SYSTEM
4. Rear Air Suspension System REAR AIR SUSPENSION SYSTEM
5. ABS with EBD & BA & TRAC & VSC System ABS WITH EBD & BD & TRAC
6. Electronically Controlled Automatic Transmission [ECT] ((A750E/A750F)(1GR-FE)) ELECTRONIC CONTROLLED AUTOMATIC TRANSMISSION [ECT] ((A750E/A750F)(1GR-FE))
7. Electronically Controlled Automatic Transmission [ECT] ((A750E/A750F)(2UZ-FE)) ELECTRONIC CONTROLLED AUTOMATIC TRANSMISSION [ECT] ((A750E/A750F)(2UZ-FE))
8. Air Conditioning System AIR CONDITIONING SYSTEM
9. Supplemental Restraint System SUPPLEMENTAL RESTRAINT SYSTEM
10. Lighting System LIGHTING SYSTEM
11. Wiper & Washer System WIPER & WASHER SYSTEM
12. Audio System AUDIO SYSTEM - DIAGNOSTICS
13. Navigation System NAVIGATION SYSTEM - DIAGNOSTICS
14. Back Monitor System BACK MONITOR SYSTEM - DIAGNOSTICS
15. Combination Meter COMBINATION METER - DIAGNOSTICS
16. Power Window Control System POWER WINDOW CONTROL SYSTEM - DIAGNOSTICS
17. Back Door Power Window Control System BACK DOOR POWER WINDOW - DIAGNOSTICS
18. Power Door Lock Control System POWER DOOR LOCK - DIAGNOSTICS
19. Back Door Closer System BACK DOOR CLOSER SYSTEM - DIAGNOSTICS
20. Wireless Door Lock Control System WIRELESS DOOR LOCK - DIAGNOSTICS
21. Key Reminder Warning System -
22. Engine Immobilizer System ENGINE IMMOBILIZER SYSTEM - DIAGNOSTICS
23. Theft Deterrent System THEFT DETERRENT SYSTEM - DIAGNOSTICS
24. Multiplex Communication System MULTIPLEX COMMUNICATION SYSTEM - DIAGNOSTICS
25. Can Communication System CAN COMMUNICATION SYSTEM
26. Cruise Control System CRUISE CONTROL SYSTEM
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.