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General Information: Notes

WARNING: This page is about a different car, the 2004 Toyota Sienna. However, it is still accessible from the selected car via links, so may be relevant.

There are many ECU controlled systems used in the SIENNA. In general, ECU controlled systems are considered to be very intricate and require a high level of technical knowledge and expert skill to troubleshoot. The fact is, however, that if you proceed by inspecting the circuits one by one, troubleshooting of these systems is not complex. If you have adequate understanding of the system and basic knowledge of electricity, the problem can be accurately diagnosed and fixed. Articles are designed based on the above principle to help service technicians perform accurate and effective troubleshooting, and is compiled for the following major ECU controlled systems:

The troubleshooting procedures are described on the following pages.

ECU CONTROLLED SYSTEM TROUBLESHOOTING

System See
1. SFI System HOW TO PROCEED WITH TROUBLESHOOTING
2. Tire Pressure Warning System HOW TO PROCEED WITH TROUBLESHOOTING
3. ABS with EBD System HOW TO PROCEED WITH TROUBLESHOOTING
4. ABS with EBD & BA & TRAC & VSC System HOW TO PROCEED WITH TROUBLESHOOTING
5. Electronically Controlled Automatic Transmission [ECT] HOW TO PROCEED WITH TROUBLESHOOTING
6. Air Conditioning System HOW TO PROCEED WITH TROUBLESHOOTING
7. Supplemental Restraint System AIR BAG RESTRAINT SYSTEMS
8. Lighting System HOW TO PROCEED WITH TROUBLESHOOTING
9. Audio System HOW TO PROCEED WITH TROUBLESHOOTING
10. Navigation System HOW TO PROCEED WITH TROUBLESHOOTING
11. Rear Seat Entertainment System HOW TO PROCEED WITH TROUBLESHOOTING
12. Back Monitor System HOW TO PROCEED WITH TROUBLESHOOTING
13. TOYOTA Park Assist System HOW TO PROCEED WITH TROUBLESHOOTING
14. Combination Meter HOW TO PROCEED WITH TROUBLESHOOTING
15. Power Window Control System (w jam protection) POWER WINDOW CONTROL SYSTEM (W/ JAM PROTECTION)
16. Power Door Lock Control System HOW TO PROCEED WITH TROUBLESHOOTING
17. Slide Door Closer System HOW TO PROCEED WITH TROUBLESHOOTING
18. Power Slide Door System HOW TO PROCEED WITH TROUBLESHOOTING
19. Back Door Closer System HOW TO PROCEED WITH TROUBLESHOOTING
20. Power Back Door System HOW TO PROCEED WITH TROUBLESHOOTING
21. Wireless Door Lock Control System HOW TO PROCEED WITH TROUBLESHOOTING
22. Key Reminder Warning System HOW TO PROCEED WITH TROUBLESHOOTING
23. Engine Immobilizer System HOW TO PROCEED WITH TROUBLESHOOTING
24. Theft Deterrent System HOW TO PROCEED WITH TROUBLESHOOTING
25. Multiplex Communication System HOW TO PROCEED WITH TROUBLESHOOTING
26. CAN Communication System HOW TO PROCEED WITH TROUBLESHOOTING
27. Cruise Control System HOW TO PROCEED WITH TROUBLESHOOTING
28. Dynamic Laser Cruise Control System HOW TO PROCEED WITH TROUBLESHOOTING