Perhaps, after releasing the 1986's Toyota figured it can make a few extra hundred bucks a pop by making it an option. LOL!
(On the other hand, mine does not have the light reminder relay; I had to make one myself.)

What motors do you guy have? I believe the controller is somewhere else. Haven;t had chance to check P/N.

 

I'll have to check on my motor. Here's a vid.
https://www.youtube.com/watch?v=0h_M...ature=youtu.be

 

I'm with Radrunner. My wipers come on automatically when I use the as squirters. 1986 Pickup DLX Xtracab. carb'd 5-speed. P/B P/S. G54 tranny.

 

in this thread, only 1986 vehicles seem to have the wiper function when pushing the washer button.

 

My 84 doesn't have it, but it does have mist.

 

Bringing back this year old thread (almost). I just took a picture of my wiper motor and noticed the numbering was slightly different than rad4runner's. I don't think a motor has to do with the wipers turning on though.