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Discussion Starter · #1 ·
Hi Folks,

I am almost ready to get my 70 Opel GT on the road after 3 years of work (14 years since it has been on the road!), but I have one last wiring problem. The short story is that the prior owner couldn't get the car running and butchered the factory harness really bad. It was a huge mess and chopped up, so I replaced it with a Painless Wiring hit and fuse box. The dash was trashed so I fiberglassed a new dash and center console, and put in VDO gauges. All of this has worked really well. Last night I got to the last thing I have to wire, which is the window wiper motor.

In reading around on the forums here I found that the foot pedal switch had some part in controlling it, but I am not sure how to wire it. I am guessing it is not just running the wires from the wiper motor to the switch...

I was wondering if anyone else has had to custom wire up the wiper motor before? Or, does someone have a simple picture of how I could custom wire it? The factory manual's wiring for the window motor didn't really help me much. With a 4 wire wiper motor, does it need some kind of solenoid or interrupter switch to make the "park" work properly?

I still have the old wiring harness if I need something off of it. Thanks for any help that anyone can offer... I am a little stumped.

-Josh
 

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The foot peddle is the pump for the w/s washer and turns the wipers
on for one back and forth wipe for each press, with key ON.
Wipers can be turned on and off with dash switch also, with key ON.
Pump could be bypassed if you don't need washers.
 

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Just Some Dude in Jersey
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I went super primitive with my set up:



The green wire is the Park wire and needs constant power. White, purple, yellow are the 3 speeds. I installed custom switches and I couldn't get one with 3-4 positions and I realized that Low speed served my needs best, so I ended up with a VERY simple wiper wiring set up using a simple On-Off switch. If you have an Off-Lo-Med-Hi switch, then you just hook up the other wire colors to the other terminals. I deleted the foot pedal and squirt bulb.
 

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Discussion Starter · #5 ·

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Discussion Starter · #6 ·
Update: I have it working with the foot pedal for one pass of the wipers.

I have green to +12v and bottom left.
Yellow -> bottom right.
White -> top left.
Blue -> Top Right.

I guess this is not correct (and I have tried various other configurations) since the wipers are only giving me one pass before parking.

I referenced the wiring diagram and it looks like the purple is normally the hot coming from the horn, which I have wired separately when I redid the harness. So, I am using the green wire coming from the wiper motor and the fuse box in its place.

I am assuming that if I had this correct then the wipers would come on, stay on, and cycle through the speeds each time I press the switch? Hope this helps explain my current problem and someone can help out.. :confused:

Thanks,

Josh
 

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Discussion Starter · #7 ·
I understand why scifiguy bypassed the foot switch once I went back to look at the factory diagrams. I just ended up wiring in two switches for low and high speed wipers into extra spots in my switch panel.

Thanks for the assist again folks.. I never would have known the green wire needed constant hot.
 

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Just Some Dude in Jersey
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Are you trying to make the foot pedal the primary on-off switch for your wipers and not have a dash switch at all? That's what it sounds like.

That won't work. The foot pedal switch is a momentary switch. Pressing it allows just a short pulse of power to get to the motor. This, I guess, closes a relay or circuit powered by the always-on green wire. When the wiper motor rotates to the "dead zone", the power from the green wire is temporarily interrupted, which lets the motor slow down and stop.

If the motor continues rotating long enough after the "dead zone" is encountered, the power from the green wire will be restored and the wipers will do another one-wipe rotation until the motor gets to the dead zone again. I have this problem in my car because I only use the driver's side wiper. The entire mechanism is designed to have the load or drag of both wipers to slow the motor during the dead zone transition. If my windshield is very slick and clean, my single wiper doesn't apply enough drag to slow the motor to a complete stop during the dead zone transition and the darn thing will keep going long after I've turned off the switch. I have to pull over and grab the wiper on the down stroke to slow it down so that it stops in the dead zone.
 

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Just low speed wiper?

Wow this has been a timely thread I just bought a wiper motor from the uk because I to am installing a painless kit because the wiring in mine was soooo butchered with the original right Hand drive conversion and I was always fixing wiring problems.
The wipers only had one speed and no park, the wires from the starter were all black, even scratching the insulation didn't show any colour.
Feeling a bit lazy at hoping for a better wiper motor got the one from the uk and it looks like its in much better condition than mine and the wires have colour.
So this has been the icing on the cake.

Thank you
Alex
 

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Are you trying to make the foot pedal the primary on-off switch for your wipers and not have a dash switch at all? That's what it sounds like.

That won't work. The foot pedal switch is a momentary switch. Pressing it allows just a short pulse of power to get to the motor. This, I guess, closes a relay or circuit powered by the always-on green wire. When the wiper motor rotates to the "dead zone", the power from the green wire is temporarily interrupted, which lets the motor slow down and stop.

If the motor continues rotating long enough after the "dead zone" is encountered, the power from the green wire will be restored and the wipers will do another one-wipe rotation until the motor gets to the dead zone again. I have this problem in my car because I only use the driver's side wiper. The entire mechanism is designed to have the load or drag of both wipers to slow the motor during the dead zone transition. If my windshield is very slick and clean, my single wiper doesn't apply enough drag to slow the motor to a complete stop during the dead zone transition and the darn thing will keep going long after I've turned off the switch. I have to pull over and grab the wiper on the down stroke to slow it down so that it stops in the dead zone.
This is not something that I thought would be possible. The dead zone as you call it is created by a contact inside the wiper motor that passes over a spot that has no conductor on it. In order for it to do what you describe the motor would have to coast a good distance and I doubt that is happening no matter how slick you think you are, or your window :cool: The contacts on the foot switch are in parallel with the on switch if I remember and using the foot switch is basically the same as turning the wiper switch on and then immediately off again which will cause the wipers to park after one cycle.
 

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Discussion Starter · #11 ·
@SciFiGuy - You are correct that I was thinking/trying to make the foot pedal work as the only switch. This is mainly because I did not understand how the wiper motor was working and that it had a separate dash switch from the factory. My car was pretty well torn apart when I bought it, and had a huge box of parts... so I never knew that switch even existed. I also didn't understand that the circuit was grounding through the motor itself.

Once I ran the high and low speed switches to two separate switches on my switch panel they both work flawlessly! :cool:

I very much appreciate the assist.

-Josh
 

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Just Some Dude in Jersey
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I've always felt that the GT one-wipe/squirt bulb on the floor to be a cockamamie gimmick. The only good use I ever found for the things is when I would trick my passengers into thinking I had voice actuated wipers. "Wipe!"......(secretly press the floor switch)......and the wipers would wipe. The squirt bulbs leak and may be to blame for many a rusted floor board. I've never found a squirt and one wipe to ever be sufficient to clean a windshield on any car. As far back as the mid-80's I routinely removed the squirt bulbs and installed electric windshield squirter pumps. Squirt, then wipe at low speed until I'm satisfied, then wipers off. I think on one GT I disconnected the one-wipe wires from the floor switch and connected the switch to the electric windshield squirter.
 

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I've always felt that the GT one-wipe/squirt bulb on the floor to be a cockamamie gimmick. The only good use I ever found for the things is when I would trick my passengers into thinking I had voice actuated wipers. "Wipe!"......(secretly press the floor switch)......and the wipers would wipe. The squirt bulbs leak and may be to blame for many a rusted floor board. I've never found a squirt and one wipe to ever be sufficient to clean a windshield on any car. As far back as the mid-80's I routinely removed the squirt bulbs and installed electric windshield squirter pumps. Squirt, then wipe at low speed until I'm satisfied, then wipers off. I think on one GT I disconnected the one-wipe wires from the floor switch and connected the switch to the electric windshield squirter.
Well other than the fact that I NEVER use the wipers on my GT (I use rainx) the foot switch is actually handy if you don't have intermittent wiper capability. I had the exact same system on my 1973 Capri and use to push the edge of the ring to do one swipe when there was just light rain or a mist when I did not need the wipers on. Just like today's one swipe with the stalk on most cars.
 

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Opeler
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I've always felt that the GT one-wipe/squirt bulb on the floor to be a cockamamie gimmick. The only good use I ever found for the things is when I would trick my passengers into thinking I had voice actuated wipers. "Wipe!"......(secretly press the floor switch)......and the wipers would wipe. The squirt bulbs leak and may be to blame for many a rusted floor board. I've never found a squirt and one wipe to ever be sufficient to clean a windshield on any car. As far back as the mid-80's I routinely removed the squirt bulbs and installed electric windshield squirter pumps. Squirt, then wipe at low speed until I'm satisfied, then wipers off. I think on one GT I disconnected the one-wipe wires from the floor switch and connected the switch to the electric windshield squirter.
Actually, for me, if/when I use the wipers is almost always via the pedal. Very convenient. Always thought this was a feature ahead of its time.
 

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Opeler
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What is the Blue wire?

So I've read the threads on the wiper motor wiring but I'm confused as to the function of the blue wire at the motor. Here's what I know:

- Green wire: "Park" with +12v all the time except when in Low or High
- Yellow wire: Low speed power
- White wire: High speed power
- Blue wire: grounded when in Park, open when in Low or High...or the foot pedal pushed

The Wiper motor is grounded and obviously uses the chassis ground to complete the power circuit.

So what the heck does the Blue wire do?
 

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Opeler
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Thanks Norbert. Do you have an electrical diagram of how this works? Ohm'ing out the switches I determined that the blue wire is grounded ONLY when the fan switch is in the off position, no connection when in Low or High, and pressing the foot pedal also opens this connection. Does anyone have an internal wiring diagram of the motor itself? My curiosity just won't go away!
 

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Just Some Dude in Jersey
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Based on this schematic....:


Dog Mammal Vertebrate Dog breed Canidae



......it appears that the blue wire probably applies momentary power to the low speed circuit, the green wire then continues to apply temporary power until the motor gets to the "dead zone" where all power is stopped.
 

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Opeler
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Based on this schematic....:


View attachment 328433


......it appears that the blue wire probably applies momentary power to the low speed circuit, the green wire then continues to apply temporary power until the motor gets to the "dead zone" where all power is stopped.
I don't think that is true Gordo as the blue wire is a ground, not a 12v power source. If the motor case is grounded and the source of the ground, why the extra ground wire? I wonder if it is a grounding shunt for the motor windings which is opened up during any run operation?
 
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I don't think that is true Gordo as the blue wire is a ground, not a 12v power source. If the motor case is grounded and the source of the ground, why the extra ground wire? I wonder if it is a grounding shunt for the motor windings which is opened up during any run operation?
I read a post again here in German language.I think I wrote nonsens! You are right with the blue wire is a ground,when all switches are in off! That means the blue wire is a brake in park postion! Then the blue wire give a extra ground to the Motor windings!If you have not the blue wire,the motor can turn and turn and turn by rain also when you push the switches off!
 
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