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General Information: Notes

WARNING: This page is about a different car, the 2005 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. This article is 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 references.

ECU TROUBLESHOOT

System
SFI SYSTEM
TIRE PRESSURE WARNING SYSTEM
ABS WITH EBD SYSTEM
ABS WITH EBD & BA & TRAC & VSC SYSTEM
ELECTRONICALLY CONTROLLED AUTOMATIC TRANSMISSION [ECT]
AIR CONDITIONING SYSTEM
SUPPLEMENTAL RESTRAINT SYSTEM
LIGHTING SYSTEM
AUDIO SYSTEM
NAVIGATION SYSTEM
REAR SEAT AUDIO SYSTEM
REAR SEAT ENTERTAINMENT SYSTEM
BACK MONITOR SYSTEM
TOYOTA PARK ASSIST SYSTEM
COMBINATION METER
POWER WINDOW CONTROL SYSTEM (W/ JAM PROTECTION)
POWER DOOR LOCK CONTROL SYSTEM
SLIDE DOOR CLOSER SYSTEM
POWER SLIDE DOOR SYSTEM
BACK DOOR CLOSER SYSTEM
POWER BACK DOOR SYSTEM
WIRELESS DOOR LOCK CONTROL SYSTEM
KEY REMINDER WARNING SYSTEM
ENGINE IMMOBILIZER SYSTEM
THEFT DETERRENT SYSTEM
MULTIPLEX COMMUNICATION SYSTEM
CAN COMMUNICATION SYSTEM
CRUISE CONTROL SYSTEM
DYNAMIC LASER CRUISE CONTROL SYSTEM