[186464]

Does anyone have wiring diagrams? At least that would be a good start?

 

[186464]

Thanks for the all the help!

 

[186464]

You're welcome! I've noticed activity on this forum has recently fallen - might be due to XMAS.

Finding adequate "free" electrical diagrams might be a stretch. You can get them from Toyota for a small fee at https://techinfo.toyota.com/

The following web page has links to diagnosis information about the anti-theft system: Sitemap

I can view a bazillion electrical diagrams for the 2011 Sienna Limited including 19 diagram files for the anti-theft system on the "Auto Repair Source" service available through my local public library's website. It's not realistic for me to download and upload all these files. Maybe your public library offers a similar service.

The first components I'd check would be the switches on the door jams. They are of a type that are known to sometimes fail and which Toyota stopped using on their more expensive cars (e.g. Lexus) around 25 years ago. An intermittent problem with one these switches could set off your alarm. Press each switch with a finger to see if they operate smoothly. If the little "piston" in the switch binds or is sloppy, that could indicate a failure. There have been threads on this forum about replacing them. I replaced a very similar switch on an early Lexus in the 1990's and it was fairly easy but did require removal of interior trim to get to it.

Thanks for the response. I thought those switches only operated the interior lights when opened? As far as I can tell they only have a single wire going to them. I held the door open with my finger pressed on the switch. I locked the door and then removed my finger from the switch and only the dome lights came back on. Alarm did not go off.

I tried looking at the link you sent me but to be honest I'm not sure how any of it is helpful. It doesn't really show exactly what I'm looking at and refers to the switches (including hood latch switch which has 2 wires) as a courtesy switch.