Electronics guru's I need help

[IMR-Merlin]

Posted in the turbo forum also, but might get some help here.

Guys I am in the process of integrating my factory wiper motor to the painless wiring harness. Does anyone know what makes the wiper motor return to the "home'" or "down" position after you turn the switch off? I can get the high and low to work and assuming the intermittent is the other wire. Do you have to use the intermittent relay as part of the system for the wipers to return home?

thanks for any advice.



Here's a pic of the project...

[rick-l]

Not a guru but a quick look at the Bentley and I would say power for the park switch comes from the interval unit.

[wwest]

Originally Posted by rick-l

Not a guru but a quick look at the Bentley and I would say power for the park switch comes from the interval unit.

Just like an electric driven antenna, the wiper motor must have a power source independent of the on/off switch.

[rick-l]

If a real guru looks at this can they explain the Bentley schematic connecting the park switch power to ground (direct short) to me? What is there in the park switch not explained.

[IMR-Merlin]

I have a white and blue wire on the bottom of the motor that looks to be the park switch. I am giving 12v constant to the red/white wire and constant ground to the brown wire.

[steely]

Not sure what year we're talking here, but unswitched power is used for parking.
In Bentley it looks like unswitched power is going to the wiper motor terminal 53a using Red-Wht for 84-89.

If you are testing on the bench, I would energize this (in order to test the parking) only after you removed power from your Blue-white side.

I went through a problem with my rear wiper once and seem to recall that the cam switch wasn't drawn accurately for the Rear. I mention this because I agree with Rick that the power is shown going to ground for the front wipers.

On Edit: Beautiful Project BTW - impressive!

[Discseven]

Originally Posted by IMR-Merlin

Nice ride Merlin!

[IS300]

you need the relay..... I have the bentley ...

[IMR-Merlin]

Damn. I'm going bare bones with this project and wanted to get rip of the intermittent relay. I have an 87 parts car for my G50 donor.

[IMR-Merlin]

Thanks for all the positive feedback. It's been a 4 year project from a car I rescued from an impound yard. Tomorrow I'll post up a pic of it on day 1. But everything including fabrication, powder coat and paint has been done at my house in my garage.

[IMR-Merlin]

This motor is out of the 82 930 but I have an 87 for parts. I am running the 53a red/white hot but it's not parking. I'll dig through the Bentley and parts car tomorrow.

Not sure what year we're talking here, but unswitched power is used for parking.

In Bentley it looks like unswitched power is going to the wiper motor terminal 53a using Red-Wht for 84-89.



If you are testing on the bench, I would energize this (in order to test the parking) only after you removed power from your Blue-white side.



I went through a problem with my rear wiper once and seem to recall that the cam switch wasn't drawn accurately for the Rear. I mention this because I agree with Rick that the power is shown going to ground for the front wipers.



On Edit: Beautiful Project BTW - impressive!

[steely]

Originally Posted by IMR-Merlin

Damn. I'm going bare bones with this project and wanted to get rip of the intermittent relay. I have an 87 parts car for my G50 donor.

Well this is different. It can be done and would operate similar to the rear window wiper. I wouldn't give up so easily just yet if I were you.

I am running the 53a red/white hot but it's not parking.

I suspect your cam switch on the wiper. The unswitched hot is only for that purpose.

[IMR-Merlin]

Ok, I was laying in bed this morning and had a thought. On the bottom of the motor, I have 2 wires which I assume go to the park switch.

This car sat from 1994 till just yesterday with the wipers in the park position. I am wondering if the switch is stuck in the depressed position!

I have the motor and linkage in the car right now for a test fit. When I pull it out later, I should be able to have continuity between the white wire and blue wire on the switch in roughly 350-355 degrees of motion. When the switch gets depressed, it breaks continuity to the red/white wire (53a) and stops the motor.

That sound plausible?

[IMR-Merlin]

The possible culprit....

[IMR-Merlin]

As promised, this is what the car looked like when I found it and a few pictures along the way.

[rick-l]

I am sure there is some way around the interval controller but until someone chimes in with how that park switch works it is kind of a shot in the dark.

Like what does that thing connected to 53a and 53e in the wipers do? wtf does that ground connection do?

[IMR-Merlin]

Ok, figured it out.

Let me start this by saying I want to really back date this and make it as barebones as possible. It's a seasonal car so no washer and no intermittent wiper.

That being said I figured out how to park WITHOUT the intermittent relay!!

On the back side of the wiper motor you have the "parking switch" that has a white wire and a blue wire connected to it. What I failed to realize was there was also a ground.



When you pull the cover off you can get an idea of how it works.




When the motor travels through it's cycle it has about 355 degrees of contact with the white to blue wire and then it settles into the "park" position and then blue wire goes to ground. Effectively making a reversing polarity switch. I am guessing that this is used to get those 3 full sweeps of the wipers after you hit the windshield washer.

so as you can see, there are 3 contacts....




so, in the factory setting and all 3 contacts in place, the red/white wire goes to the blue wire and while the wiper is not parked you have 12v going through the switch to the white wire that goes to terminal 53e. When the motor hits the park position, the white wire goes to ground. So terminal 53e is now grounded.

So what I did to make this motor work the way I need it to was to cut the contact that goes to ground so that terminal 53e will ONLY be 12v+ for the cycle and NEVER go to ground.



I then built a jumper from terminal 53e to the black/violet (intermittent) wire in.




So during the sweep of the motor, no matter what switch is on (low or high) the black/violet wire gets ignition switched 12v+. So if you were turn the wipers off, they will still have 12v to return to home.


I will just have one "dead" position on my wiper switch which I will deal with.

As for the washer pull switch, I am using this for the horn (removable wheel).

[IMR-Merlin]

ha, I just came on to post. I will need to run a simple relay to take power away from the Red/white wire when I have the switch on. If the red/white is connected, I only have one speed. Simple fix and if I wasn't using the "pull" position of my switch to activate the horn, I would probably gut the whole wiper system out of the donor car.

It's doable, just not as simple as I wished it would be.

[rick-l]

Thanks for the pictures. Answers a lot of questions.

[IMR-Merlin]

Ok, so here is the final result of my day. I have decided to use all 3 positions of the factory wiper switch.

position 2 = wipers low

Position 3 = wipers high

intermittent position 1 = returns wipers to park

This way I can have all factory connections with no additional relays and I use all 3 positions of the wiper switch.

wiring is straight forward. 53a is now connected to the 12v out from the wiper switch to be energized with the position 1. So if I use the wipers, I just need to put the switch in position 1 (intermittent) until the wipers park, then I can leave it there or turn the wipers off.