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Discussion Starter #1
Hi all
Need some electrical advice
I posted a thread a few weeks back regarding the wiring on my 1600 gt J. Early 1750 style. Bit of a mess where someone had wired it with out a foot switch.

So I have now got my new toggle switch, foot switch and wiper motor all wired up, I have gone through the wiring diagram and believe it's wired correctly.

I flick the switch and the wiper motor turns and after a few seconds the fuse pops:frown2:

The fuse doesn't blow with the wiper motor disconnected. But then there isn't any load. Also note the wiper linkage is disconnected.

Any tips greatfully received.
 

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A high current draw or short exists somewhere... Can you bench test the motor and check the amp draw with a meter? Also, check the wiring from the switch to the motor, connect a lamp or something else in place of the wiper motor and see if the fuse blows.

Good ground(s) and clean connections are paramount.


Good luck,

Doug
 

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Discussion Starter #3
Thanks Doug,
I guess the motor is just earthed direct through the motor casing and the body? Any other grounds to look for.
I'll have a look at seeing how to bench test the motor. I do have a probe which can deliver voltage
 

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I guess the motor is just earthed direct through the motor casing and the body? Any other grounds to look for.
That's right, the motor grounds through its casing. Good grounds and clean connections are essential when you aren't getting enough current to the motor (like when its running slow or not at all). Your problem is that you are getting too much current to the motor. So go ahead and check the grounds & connections, but don't expect that to prevent fuses from blowing.

I'll have a look at seeing how to bench test the motor. I do have a probe which can deliver voltage
It would be ideal to have an ammeter in that circuit, and see how much the motor is drawing. How does the wiper motor's peak current draw compare with the rating of the fuses you have been blowing?

I flick the switch and the wiper motor turns and after a few seconds the fuse pops
Define "a few seconds". Does it run long enough for the wiper blades to make several full swipes? Or just a partial swipe? (yea, I know - the linkage is disconnected). The reason I ask is: The WW motor-trans has some contacts that control the park function. Is it possible that something is miswired, allowing the the motor to run until those contacts engage, and that contact engagement is what pops the fuse?

And how fast does the motor run? Is it possible the gearbox grease is dried out and creating so much drag that the motor is almost stalling and drawing high current?
 

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Discussion Starter #5 (Edited)
Good point regarding draw. i would say no more than 1/2 to one sweep.

So let's start with the new toggle switch. this is new.

It's a new 5 pin switch. Pins 1,4,6,7,8.
These pins don't relate to a wiring diagram. I found a forum post and followed that, but this could be wrong for a 4 wire motor.

Are the switches fitted upside down, I.e toggle pointing up, numbers upside down?
Also what is the off position, up? When in the middle position this would suggest fast looking at the voltage reading on the wires and bottom position being slow. That's does seem a bit backwards...
Sorry I have nothing to compare with and a bit of a newb with alfa's

I have connected
Grey pin 1
Blue pin 4
Blue / black pin 6
White / blue pin 7 (doesn't get a voltage whateve the switch position is)

Thanks for any help
 

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Good point regarding draw. i would say no more than 1/2 to one sweep.

So let's start with the new toggle switch. this is new.

It's a new 5 pin switch. Pins 1,4,6,7,8.
These pins don't relate to a wiring diagram. I found a forum post and followed that, but this could be wrong for a 4 wire motor.

Are the switches fitted upside down, I.e toggle pointing up, numbers upside down?
Also what is the off position, up? When in the middle position this would suggest fast looking at the voltage reading on the wires and bottom position being slow. That's does seem a bit backwards...
Sorry I have nothing to compare with and a bit of a newb with alfa's

I have connected
Grey pin 1
Blue pin 4
Blue / black pin 6
White / blue pin 7 (doesn't get a voltage whateve the switch position is)

Thanks for any help
My experience with this is, if you have a 4 wire wiper motor it means that you have 2 speeds and automatic park. For me that means that you need a toggle switch with 8 pins, wired as follow, its in Spanish but I think its understandable.
 

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Discussion Starter #7
Now working !!!

New 4 wire motor, new foot switch and a new after market 5 pin toggle switch, now all working as it should and parks correctly.

Blue/white needed to be on pin 8 (not 7 as per another post)

So
Pin 1 grey
Pin 4 blue
Pin 6 blue/black
Pin 8 blue/white

(Pins 2,3,5 have no terminals)

Position,
top = off
Mid = slow
Bot = fast

Hope that helps someone
Car is a 74 1600 gt junior South african car (1750 dash pre unified model)

Thanks for your help.
 

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Wiper Foot Switch

Hi Guys,

I've just purchased a 1971 1750GTV which had the foot switch removed and I can't get the new one to work either. When plugged in everything works OK both speeds and park on the wiper switch, however, when I use the foot switch the fuse blows immediately. All plugs look as though they're fitted correctly so I don't know if I have a faulty switch or faulty wiring, any ideas on how I could test it and the wiring circuit as I'm not that good with electrics.
 

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Discussion Starter #9 (Edited)
Must be miss wired at the foot switch, my car had the foot switch missing and a work around had been but in place that was very different than any wiring diagram I found.

I guess to start with check the wires to the foot switch are connected to the correct pins on the foot switch.

Post here shows the foot switch terminals . Just cross check your wiring with this
http://www.alfabb.com/bb/forums/gt-1963-1977/159284-washer-foot-switch-operation.html
 
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