I just had a similar issue where my locks were locking and unlocking randomly. went reading on this forum thinking something is fried. initial thoughts were the door lock acuator failing or the body control module.
this started happening after I had the driver's window open while it was drizzling outside that I didn't notice. The next day the locks would lock and unlock themselves (i have video of it if you want) and the security system turned itself on while I was just sitting in the truck with the door open. totally wierd stuff.
Thinking the worst , I went to Oakbrook Toyota of Westmont (where I bought my runner cause it's under extended warranty to see what they thought.) Service manager thought either bcm or door lock acuator as well.
Said they would need to inspect first to see if it was even covered. My appointment is this Wednesday.
This past weekend it was pretty warm outside (80) in Illinois and now it looks like the issue resolved itself. I might be premature in this, but since Saturday, the locks haven't been unlocking and locking themselves and the security system has been fine.
fingers crossed that it was just a bit of moisture in the locks that caused this!
Let yours dry out a bit if you can and see if the issue goes away. I sure hope mine did!
metramm
2006 4runner 4x4 v6
145,000 miles