Hi Folks,
Over the past few weeks I've been obsessed with finding my own way to make an intermittent/delay wiper module for my truck. I've found it difficult to find a plug-and-play unit from the junkyard and also don't have the time during junkyard hours to go driving long distances to a junkyard to NOT find the parts...

That being said, I've managed to find a schematic and build an electronic circuit that will properly work. However, in order to make the unit properly work I need to tie in into the wiper park circuit so I can have a complete cycle of the wipers as opposed to having the wipers just stop mid-windshield.

SO can anyone explain to me particularly how the park feature works?

Obviously when the wiper switch is turned on (on a non-delay unit), power is applied to the low or high side of the motor and it just does its job. When you switch the switch off I'm guessing that power is applied to the park circuit and the motor allows power to continue the cycle? Is this accurate? Also, when the park circuit is engaged, what particularly is engaged? Does the switch send +12v to the park circuit or does the switch ground the park circuit? I think I have the concept down I just don't know how in particular the park works power wise.

As soon as I get my prototype up and running I'll do a write up. I managed to buy all the parts from good old radio shack so if anyone is cheap and gets the satisfaction of 'doing it themselves' like me, you will love this project!!!

Thanks for the help!

 

Al - I will check the EVTM tomorrow to see if it explains the park circuit. Will let you know.

 

Al - See if this is what you need:

 

Gary, that book is for a "Courier" which was actually a Mazda built vehicle. Not sure that diagram is accurate for a Ford.....

 

I just turned to the back of the book where it said. Guess I need to look again.

 

Gary, thanks anyway. I really appreciate it. In the meantime I may have come across some additional information (from google image search) and came to my own conclusions. See my pic below but here's what I have concluded. If anyone cares to comment I would appreciate the input. Anyway, based on the terminal pin-out (the pic with the wiper switch in it and continuity check) I believe that when the wiper switch is placed in the off position, the wire to low side of the motor becomes common with the park wire. Does this make sense to anyone? I don't really want to test it on my truck without having a second opinion. The last thing I need right now is to blow up my wiper motor...

If it is this simple I'm going to be a very happy person as I'll pretty much be ready to roll with my wiper delay unit!!!!

Let me know your thoughts.

 

Al - Sorry, but I cannot read that. It is just too blurry. Having said that, I am sure you are right because that is also what the diagram and write up I sent shows.

 

Yea I'm working on blowing it up now. I'm having trouble posting a larger image through the user albums.... stay tuned!

 

OK I didn't realize there are two ways to upload photos. One being (and what looks like the old way) the user gallery and the other being user photos or something like that. I've edited the original post with the pics for slightly larger images.

Hope this is clearer!

 

Much better. Thanks. And, if you compare that with what I posted I think you'll see they are effectively the same.

 

In the picture below, visualize the arrow in the wiper motor box swinging back and forth each time the wiper cycles. That's the cam switch. It swings back and forth from the words "park" and "run".

When the switch is in low, the motor is supplied directly by the wiper switch. When the switch is off, the motor is supplied by the cam switch(the arrow in the diagram). If the motor is anywhere but park, it's going to keep running till the arrow swings over to "park" and the motor stops.

 

Dave or Gary,
You wouldn't happen to have a page with the delay wiper switch workings? I'd love to adapt/incorporate the factory delay switch into my DIY wiper delay...

Thanks for the correction Dave. I'll revise my schematics. This makes more sense.

 

I will look tomorrow to see if the EVTM has the delay wiring diagram.