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04 GT Wipers have me stumped.

7K views 10 replies 2 participants last post by  FlyinOrRidingDa 
#1 ·
Guys,

I'm hoping someone can help me figure this out. My wipers don't work at all. I've replaced the wiper motor, combination switch, GEM module fuse 26 all 3 relays associated with the wipers along with every relay that's not listed in the owners manual, still nothing. everything else in the car works fine no niks in the harness anywhere my washer fluid pump even works.

The only thing discerning to me is a 2 prong grey plug that sits directly above where the floor heat vent comes out, it comes out of the main harness and is directly next to the flasher relay. I can't see anywhere this plugs into (it only has about a 3 inch long pigtail) and I'm not even sure if it's associated with the wipers.(possibly for a feature my car doesn't have?) I've looked at a couple cars in junk yards and they have a separate wiper module my car does not have this! Or if it does it's not next to the gas pedal like the 99-02's the wiring is specific to 03 04.

Anyone have any Ideas? This is driving me nuts!
 
#2 ·
Let's slow down changing parts and let's do some more testing.

The first test I would do is to CONFIRM the wiper motor ground black (BK) wire. Start by measuring the Ohms from the wiper black wire back to battery negative with everything off. Should be low. Even better use a test light between the black wire and battery positive.

It might help to post the wire colors. Or better yet a picture of the connector.

What has been done to trouble shoot the run/park switch inside the wiper assembly? Was JUST the wiper motor replaced?
 
#3 ·
Ground is fine the steady 12v that is constant to the motor is there the old motor actually worked when I jumped it from the battery... when doing this I used the ceter black wire as a ground and a positive jumper off the battery. The center black ground and the green directly next to it (towards the right if your standing on the driver side) read as they should 11v engine off and 14.4 engine on. The other three wires test 0 (the white, blue with red stripe, and brown with pink stripe) tested all three on every wiper setting...nadda.
 
#4 ·
Update Ohm tested my ground to the wiper motor tested 0.02. Then I directly grounded the black wire on the motor. Still nothing. I read something about a resistor on the "stack" on another forum I have no idea what that person meant does anyone know where this resistor is located?
 
#5 ·
The wiper circuit is one of the more complex circuits. Best to do trouble shooting with a set of wiring diagrams and Ford service manual. In the manual are a set of pin point tests that will provide the decision tree to solve the problem. IF interested in getting a set for your self I may be able to help. PM if interested.

You have not answered all of the questions. What are the wire colors and a picture of the connector in question. IF this connector is the wiper control to the GEM then it's not a surprise that the wipers don't work. Does one of the wires happen to be YE/WH? The GEM YE/WH wire is part of the run/park relay. Tell me what happens if the YE/WH wire is grounded to a known good ground with the key on.

The YE/WH wire can also be picked up in the BJB at the run/park relay.
 
#6 · (Edited)
To answer your question in your first response The new motor came complete with the switch. I actually exchanged the new motor just to see if may be a got a bad unit, to no avail. I am very interested in in getting a set of the ford manuals! Also I really appreciate your help! I attached a photo of my mystery connector it's in the middle of the car there no way I can see it reaching the GEM nor is there a place to plug it in... ( the black thing underneath it is the floor vent)

One more thing I found two cut wires on the side of the drivers seat a purple with white stripe and a white with purple stripe what I found odd when re butting them was they both lead back to about the drivers seat in the rocker but both lead back to the firewall?

Also my mystery plug has no voltage to it and an Impotence of around .7
 

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#8 ·
Not sure that you are going to like the hot wire option. The GEM has programming inside it that "bumps" the Run/start relay for a short period until the wipers move off of the park stop. So to be able to have a simple run on/off switch you will need to rewire the parking switch inside the wiper assembly.
 
#10 ·
If looking for a guess on what's wrong with your system IMO it's most likely:
  • Bad GEM ground
  • Bad GEM

In the case of a bad GEM ground that should be an easy thing to test for. And if it's is your problem an easy fix. Have you done a recent radio install? IF so, a bad GEM ground should go to the TOP of the list as the radio and GEM share a ground.

In the case of a bad GEM module, that too is a straight forward swap.

The above options retain the factory feel of your car along with the delay wipers and two speed control.

To me it seems sooooooo much easier to repair the system that you have rather than hack up factory wiring to get around a system that is difficult to understand.

Frankly the cost of a new GEM would have been much less than the cost of the other parts already replaced.

But to each their own.
 
#11 ·
Hot wired it with a 3 way switch position 1 run position 2 park position 3 off. Wipers work great now no delayed or high speed but I rarely used those anyway. kept the factory ground on the plug and the constant feed. I'm happy problem solved pretty clean install as well if I do say so myself! Thanks for all your help WM!
 
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