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Discussion Starter #1
Ok this just happened yesterday so I'm trying to figure this all out soon. Supposed to rain every day this week, so It's into the garage. All 4 windows will not work. Driving to work with passenger side and driver's side windows down and they don't go up. Passenger side won't go up with the passenger side control. When pressing any of the buttons it will not even draw from the battery. I checked the breaker fuse in the box for continuity and the fuse checks out. I started testing the drivers side master switch. Started checking the leads with an voltometer/ohm's meter. Only a couple of the leads have power going to them. The lock switch get's power, and something else down the line. Other then that i'm getting .001 volts from the other leads. I checked the lockout button, it works, when depressed no power to it, when in the unlock position, power comes. So I'm not sure where else to start checking. I have a '91 Helm's Manual, which shows a window power relay. Thinking it was this I called the ford dealership to see if they could help me find it. The parts guy said it's only shown from '90-'93. So there has to be a relay or something that's not allowing power to pass to the controls for the windows. I read a post for a 2.3L having the same problems, same year '89 and vert, and someone mentioned there is somekind of power safety something behind the dash towards the A Pillar. I want to isolate and confirm this before I start tearing the dash apart. Thanks

 

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There are no relays in line. Power passes through the driver's side contacts and through the harness, but no other devices.

On my 89 LX, it was the contacts in the window switch.

Take the switch out and get a stiff piece of thin cardboard, like a matchbook cover. Soak it in WD40. Drag it carefully back and forth between the contact points of the switch. There are two of them in each switch. You can also, if you know what you are doing, bend the switch contact spring bar so the contact buttons meet centered and flat.

DO NOT do that if you do not fully understand how to bend the beryllium copper spring metal. Just clean.

This may not be your problem, but my car had two out of two dirty.

Tom
 

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Discussion Starter #3
Ok so all the power for the windows, even before passing to the passenger side door goes through the master driver's side switch? yeah I'm not sure why it would have all of a sudden just stopped working. So should I pull every switch out and clean it as described? And could just one of the switches be throwing the other switches out? I'm just surprised that it would all of a sudden stop working, which includes all 4 windows. So this is the last thing it could possibly be then. Well I will have to try this cleaning technique when I get back from this weekend. Thanks a lot and I'll let you know if this works for me. If not then I guess replacing the whole switch might do it as well.
 

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You could have a broken wire or bad plug someplace. I'm only saying in my 89 the switch contacts tarnished and failed to make contact, and this killed my system. The power door lock on the passenger side also failed because of tarnish, as did the dome light switch on the dimmer. This is VERY common in dry contacts.

DO NOT use anything abrasive on contacts. WD40 on a soaked thin cardboard works very well to polish contacts.

If you are skilled in trouble shooting, download a schematic and trace the wires with your voltmeter or better yet a test light. A test light is better because it will show high resistance connections as no light, while a voltmeter can read full voltage on a high resistance non-working connection unless the circuit is being loaded.

If you are afraid to take a switch apart, just remove it from the car and spray WD40 in the switch while working it back and forth. It won't hurt the switch to do it this simple way, although it is not as good as getting at the contacts and burnishing them with something SOFT.

Tom
 

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Discussion Starter #5
So before I even decided to clean the contacts and all I figured I'd test the door panel leads first. I have 3 pictures of what everything is. I tried shorting the windows by connecting a wire from the 12v lead on the door panel to either of the switch leads. I get no movement from any window. If i test the connection between the bottom 2 leads i get a good 11.78v power and ground. I'm not sure about the lockout switch. On the copper board it it breaks the connection when depressed to the very bottom lead. There is no power going to it or coming from it seems. I don't have a wire diagram, which would help me so much better. But can someone see if they can trace this lead and see if it is a ground or power? I'm not sure why with me connecting power to any of the leads on the door I get no window movement.
 

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Discussion Starter #6
anyone have any idea's, or a schematic for these wires? My helms manual does not have one. Guess I will have to buy a chiltons for a diagram
 

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You are certainly free to jump wires like that, but it will NOT make the motors run. It can also screw things up. It is generally a BAD idea to jumper things unless you fully understand the circuit.

The motors in the windows are all DC permanent magnet motors. They are like one of those little dc toy car motors. To reverse, the polarity of the applied voltage must be reversed.

This means the switches are DPDT (double pole, double throw) switches at a minimum. Jumping the plus over does not work because they have no minus path. To test the switches all you have to do is connect a meter across the motor. That would be one lead on the yellow/red wire, and the other meter lead on the motor red/yellow lead for the passenger window. For the driver's, it would be the yellow wire and the black/white wires.

If you have full voltage across those two leads of 12-15 volts when the switch is depressed, then you have a bad motor. If you don't, you have wiring or a switch issue. 90% of the time it is one or more dirty switch contacts, although it could be a broken wire or bad plug.

The Pink wire is the feed from the supply. The pink wire should have 12-15V to ground when the key is on.

The black wire is the ground. At the switches it should ALWAYS have around 0 volts, perhaps up to a fraction of a volt, to the vehicle chassis.

Then you have a simple polarity reversing DPDT switch that feeds that ground and hot to the motors. The passenger side GROUND feed is through the right hand switch on the driver's door. If the driver's switch is SNAFU, then the passenger window won't work because it won't have a ground. If the black ground is messed up on the driver's door switches, NONE of the windows will roll.


You could PULL THE SWITCHES OUT and then try to apply power to the motors, but you would have to apply a positive and negative voltage. BE SURE IT IS FUSED. If you read another thread on this forum, someone connected a CD player without a proper fuse and blew the computer out. Normally that would not happen but these are old cars and the grounds are often bad, so you run a risk of blowing something out if you have an unfused or improperly fused lead that hits something that is grounded. So if you are going to test the motors, PULL the switches and run TWO wires to the battery and fuse the positive wire. Otherwise you run a risk if the car has developed ground loops or ground connection issues.

Myself, I would spray WD40 in the switches and rock them back and forth about 50 times and see if they recover before testing anything. It will never hurt them to flood them with WD40, so long as you let them drip out before installing them.

Nearly 100% of the time this will fix them, although direct non-abrasive rubbing of contacts is the longest lasting cure.

Tom
 

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Better then WD40,
Go to Radio Shack or Best Buy may even have some, music store too.
Get Contact/electronics cleaner.
Comes in a can like WD, with a red straw/tube.
It drys better and is made to clean off the corosion and gunk on those contacts.
As for going out all of a sudden, replace the fuse regardless of what your seeing on the meter, some times its got a hairline break, and wont go off untill its hot.
Also check for ground between the Motor and door, and door and like the dash.
 

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I disagree. In this case we do not want a totally dry contact, nor anything real strong on the plastics. I would never trust Radio Shack quality.

These are unplated high current low voltage contacts. They fail from surface oxides and other contaminants. A light film of silicon would actually be best, but the oils from WD40 are good enough.

If this was a high-voltage switching system that could carbon track or even a silver-flashed contact a drying type cleaner would be better. This is not the application for a totally dry contact. A light coating is actually better, the WD40 actually dries too much but the good stuff is now all removed from the market.
 

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Been using it on Electronics, DJ, Sound and Lighting equipment for 20+ years
I have NO hesitation recomending that stuff, Even the Radio Shack stuff.
 

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Discussion Starter #11
Ok so I'm going to try to spend time tomorrow on fixing this problem. I'm going to replace the breaker switch in the box to see if that's the problem which I'm hoping it is and clean the contacts. Looking at it, some of the contact points show a buildup of carbon. In the second picture I uploaded which are the wire leads coming out of the door. When I test the voltage from the bottom 2 leads, the ones that the circles are directed towards each other I show a good 12v between them. So this is showing me that I'm getting good power going to the switches. And If i test the very bottom lead, the one that's by itself, this is where the lockout button is, should I be getting any power going through this as either a ground or a 12v source? Would I still be getting 12v with a bad breaker switch? I know it can't be my motors as all 4 windows stopped working all of a sudden.
 

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You could get power with a bad breaker.
It could be real weak. It can pop back and forth while useing it.
I just replaced mine tonight, along with cleaning the contacts.
I dont get as much hesitation now, when i hit the buttons.

My main (drivers Door) set had some Arcing/Carbon as well. Tiny piece of real fine emery and cleaner, cleaned them right up.
 

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Discussion Starter #13
Ok well I just replaced the breaker and the switch after cleaning all the contacts and I'm not getting anything. No windows up or down. I did just come to a realization though. When I bought the car the guy previous did a 5.0 swap. It's been 7 years since I've owned the car so I can't get in contact with him to see if he used a 90-93 harness or a 88,89 wiring harness. The only other thing I'm thinking that it could be, if it's a 90+ is the relay. My '91 helms manual just says remove the LH cowl, remove the screw and remove the relay. I've got the driver's side kickpanel off, which I'm thinking is the correct panel. If anything where would I be able to find this relay if it is a '90+ harness?
 

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First, you can not measure 12V without a LOAD and expect anything meaningful. Either use a test light that draws modest current, or load the wires.

Second, re-read what I wrote about the circuit and the grounds. Here it is again:

The motors in the windows are all DC permanent magnet motors. They are like one of those little dc toy car motors. To reverse, the polarity of the applied voltage must be reversed.

This means the switches are DPDT (double pole, double throw) switches at a minimum. Jumping the plus over does not work because they have no minus path. To test the switches all you have to do is connect a meter across the motor. That would be one lead on the yellow/red wire, and the other meter lead on the motor red/yellow lead for the passenger window. For the driver's, it would be the yellow wire and the black/white wires.

If you have full voltage across those two leads of 12-15 volts when the switch is depressed, then you have a bad motor. If you don't, you have wiring or a switch issue. 90% of the time it is one or more dirty switch contacts, although it could be a broken wire or bad plug.

The Pink wire is the feed from the supply. The pink wire should have 12-15V to ground when the key is on.

The black wire is the ground. At the switches it should ALWAYS have around 0 volts, perhaps up to a fraction of a volt, to the vehicle chassis.

Then you have a simple polarity reversing DPDT switch that feeds that ground and hot to the motors. The passenger side GROUND feed is through the right hand switch on the driver's door. If the driver's switch is SNAFU, then the passenger window won't work because it won't have a ground. If the black ground is messed up on the driver's door switches, NONE of the windows will roll.


You could PULL THE SWITCHES OUT and then try to apply power to the motors, but you would have to apply a positive and negative voltage. BE SURE IT IS FUSED. If you read another thread on this forum, someone connected a CD player without a proper fuse and blew the computer out. Normally that would not happen but these are old cars and the grounds are often bad, so you run a risk of blowing something out if you have an unfused or improperly fused lead that hits something that is grounded. So if you are going to test the motors, PULL the switches and run TWO wires to the battery and fuse the positive wire. Otherwise you run a risk if the car has developed ground loops or ground connection issues.



Tom
 

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Discussion Starter #15
Ok, ignition on, with or without the switch being depressed I am getting no voltage between the leads on the drivers side you described. I'm in the process of checking which wires are the grounds and such and they all thus far seem good.
 

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ok well all the grounds check out, along with the power. So i'm not sure where to go from here.

Get about 10 feet of medium speaker wire (16 to 12 gauge).

Strip it back a little bit at one end, and a couple inches at the other end.

Connect two or three stands of the longer stripped end, NOT the whole wire, to the positive and negative posts of the battery. Or use a small lawn tractor battery if you have one. This will "fuse" the ends at the battery by running it through a skinny end.


Pull the switches out.

Touch one of each conductor to each end of the motor leads. See if the motor tries to run. Reverse the connections and try again.
 

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Discussion Starter #18
Ok so i did what you said with the leads from the wires and the battery. The motor does try to move when I run the wire from the battery to the leads for the driver's side window.


Here's the wire color that goes into my driver's side switch,

Yellow-white/black - Drivers Window
yellow/blue-red/blue - Driver quarter window
yellow/black - red/black - Passenger window
yellow/black - red/black - Passenger quarter window

Black - Ground
Blue/Black - Hot
Red - No power or ground - This is the lockout button.

Testing those 3 with the switch off gave me those results.


Ok so the Red that goes to the lockout, I turned my multimeter down to 2v, and I'm getting a .015 reading when testing the hot to it. The only other 5 wires leading into anything are for the unlock switch.
 

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Discussion Starter #19
Ok so I got some wire ran my fuse breaker into the wire connected it to the window leads for both drivers side and passenger side and I got them up. So now at least I can drive the damn thing again.
 

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Ok so I got some wire ran my fuse breaker into the wire connected it to the window leads for both drivers side and passenger side and I got them up. So now at least I can drive the damn thing again.
Good. That means the motors all work.

Following the voltage is like following a road map. Don't you have anyone close who understands wiring that can help you??

Tom
 
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