My '85 runner is finally getting dragged out and recommisioned! Mostly minor problems and my son and I are knocking them off together. One problem which has history is that the rear wiper for some reason doesn't 'park' properly anymore. Can someone walk me through the methods Toyota employed to 'park' this wiper before the window can be activated?
I'd like to know if it can be blamed on a component such as the 'power window relay' located behind the panel on the left side interior next to the inertia reel for front seat belt and if it is, how do I test it? (what else can it be)?

The position switch indicating the wiper is parked still works the mechanism just doesn't trigger it as it doesn't return to parked. I've found that if I disconnect the one wire from that switch then all other functions work I just have to get out and 'park' the wiper physically to avoid trapping the arm/blade in the window when winding up, not the end of the world but........... I'd like it to work properly to avoid invoking 'Murphy's law'.

I've poured through the forums and come across some pretty useful informative and well thought out stuff and of all the forums that deal with 4Runners and Toyota 4x4's this site takes the cake. I hope someone out there with the wealth of informtion I need can drop it into layman's terms and help us out, I can;t wait to get my son out on the road and trails on our good old girl from Texas lol.

 

what do mean by "properly"?
The reason i ask is mine tended to hang up just enough to interfere with the back window operation, meaning that if I rolled my window all the way up I'd crush the end of the blade.
I got a different blade assembly and now it works great. Both blade assemblies were Toyota, but the one that works is shorter.

 

Hey Jim
What I mean is I expect the arm to 'seat' up on that ramp above the window when parked, I guess it doesn't reach that ramp each time it 'wipes' back and forth only when it is switched off from wiping duties so it must get a signal to 'park' and when it does it will close that switch to show it is parked properly.
Obviously yours does activate the position switch showing 'parked' otherwise you couldn't open your window, unless you've disabled that switch as I have done in the past.

 

If you have an aftermarket wiper blade on your vehicle getting the small toyota one might help. but here's an image i found, showing some sort of sensor at the wiper pivot. No idea what it does, and it's not listed seperately .

 

Yes I see that sensor, it is the 'parked' position sensor, officially named as "REAR WIPER RETRACTION DETECTIONS/W" on the wiring diagram. I found that if you unplugg the single wire that leads from that sensor into the 6 termnal plug that you have to disconnect when removing the wiper motor assembly then the wiper and washer system still works and the window will work also but of course the wiper never 'seats' into the 'park' position when finished. That's why I unlugged it (it actually has it's own bullect connector between the 6 pin block and the sensor, you can see it in your photo, almost cetre of your pic, red/white wire in bullet connector).

I can only assume at this point that the Power window relay' serving the rear window has an inbuilt function to 'park' the arm/blade when finished wiping.

Can anyone shed light on that function? Maybe I'm over thinking it?

 

This manual was from a Toyota body electrical class for techs. This was published in 1988, so relevent. I tried scanning the pages, but the binding wasn't making it easy. I'll try and get betterimages. but it seems the parking is done via notched cams in the motor housing.

 

Hey Jim thanks for your help, I have a tough time reading that but yes I see it mentions a notched cam, it also talks about two speeds for the wiper, is it referring to front wipers here? I don't recall having more than one speed on my rear wiper. Good manual, I'd love to get a hold of one of those.

 

You have to remember, this manual was for tech classroom training purposes by the factory, so the info in the book covered the way components worked and systems were designed in all models. So if the pictures don't look exactly like what you have don't be surprised. But the way it worked should be very similar. This book doesn't have diagnostic procedures, either. Just an overview.
it does show front and rear wipers in a schematic, but delves more on the front since it’s got more features.
i dunno where you could find this, it was a training book. But techs were allowed to keep their copy once the class finished. So maybe eBay?
I'll get better images tomorrow.

 

Hey Jim,

Did you by any chance get better copies of those pages? I've re-installed the wiper and it operates, I just have to watch where it is when I switch off so it seats 'close' to where it should be, I then have to make sure I seat it fully by hand so it lifts off the window and allows opening and closing with out trapping the blade. Not the way I remember it, I seem to remember it having it's own extra moment to fully seat when switched off, I don't think it would stop just anywhere by design when switched off? Do you have a functioning rear wiper to compare the action?

 

Ok. I deleted my first images and replaced them with new ones. Take a look.
Sorry they're so big. I'm still waking up. More coffee.

 

Thanks Jimkola, I see they are clearer now, I have been offline for a few days, life getting in the way lol. I also did go to look locally at an '86 with a diesel conversion, nice conversion, clever petrol heads ha ha.
We had a bit of a chat regarding all our annoying obscure problems and the rear wiper came up!
It appears that there is a function built in to the 'gearbox' to the wiper and I investigated when i got home. I haven't quite figured it out yet, I removed the cover to expose the workings and discovered there is a solenoid in the centre of the gearwheel which when activated engages the 'park' function. The park function relies on a different gear (activated by the solenoid) which winds the wiper arm that little bit further and so forces the arm to lift off of the window by virtue of the little ramp built onto the arm. When it is successfully 'parked' a shaped lever on the inside depresses a switch which is the lockout switch for the window up/down function. At that moment the mechanism trips a micro switch on the solenoid thus ending the maneuver. Writing this out convinces me that the module behind the wall panel beside the left rear passenger is probably to blame as I read somewhere here that someone took it apart and found two relays in there, i think one of those feeds the 'parking' solenoid in the wiper gearbox. The risk is taking it apart and screwing the whole affair up. Do you know if those modules are available?