Front Windows Inop - is this common?

Hi everyone - I am in the process of trying to resurrect a 85 Cabrio QV that was stored for a couple of years, and as the new owner I am finding all kinds of electrical problems. Most I have been able to resolve through Fchat, but a few I'm stuck on and could really use some help on!

The front windows (both left and right) have no motion whatsoever. They are currently down, and when I hit the console switch there is no motion or anything. I have replaced fuses, relays, and lubricated the switches & cycled them a lot. Everything else in the doors work fine (lights, power locks, power mirrors) but the windows won't budge. I pulled panels, and stuck a multimeter on the window lift motor leads while connected with ignition accessory switch on. Without pushing switch, no voltage - when I move up or down on switch I get +5vdc and -5vdc....this tells me all my switches are working at least!

Is this a case of not enough voltage getting to the motors? I measured with the leads still connected - should I be seeing 12Vdc instead? Is it safe for me to disconnect motor wires and connect leads direct to a spare battery and see if that makes the motors run? It doesnt appear to be a mechanical blockage, and once I get the motors working I have white lithium that I will lube up with (just did it to rear windows and they work great now!).

Not sure if this is related, but the glovebox does not open either. I have also cleaned the switch, changed fuses and relays, but still cannot get it to open - are these related problems?

Any help would be appreciated! I've traced through the wiring diagrams in detail, and verified connections best as I can but still no luck! Thanks!

 

I did try to clean the switches using an electronic tv tuner cleaner from Radio Shack - it did help on the rear window switches but no luck on the others. I did it with the switches still installed in the console. I will remove the switches from the console and give them a more thorough cleaning and cycling.

I did try to lift the windows by pushing them up (have panels off so can access them inside the door) but no luck - would not budge at all. Is it safe for me to connect 12VDC battery direct to the motors? If 5V is low, should it be 12V normally? If that is the case, that may be enough to get them moving, then I can pull up on the windows, and get the old grease out of the tracks. If I need to regrease the main motor, do I need to remove it from the window/car to do that, or can it be done with the unit still installed?

 

The rear windows are power, and they seem to work ok. They did have the problem of old/bad lube, but once I cleaned the switches it helped a lot. I then cleaned out the old dried grease and relubed it with the white lithium per everyone's suggestions - back windows go up and down no problem.

The car was stored inside here in the Los Angeles area, so it was never subjected to direct weather, temp extremes, or humidity. There is absolutely no sound whatsoever from the motors - they are totally silent. I did measure so I know for a fact there is voltage to the motors, but at only +-5V. Are these motors designed to operate at 5VDC, or do I have some kind of voltage/current drop somewhere? If they are designed to operate at 12VDC, then I will connect up a battery direct and see if that helps - but would like to know if that would be safe to do. Last thing I want to do is be dumb and fry my window motors!!

I will try to swap the front and back window switches later to see if that helps - thanks!

 

I will give this a try today, but if the cutoff switch engages where and how do I reset it? As for the lubrication, other threads said not to use WD40 so I have white lithium grease that I was going to apply to all moving parts.

 

I tried everything suggested this weekend, and had some success. I disconnected the motor wiring, tested it seperatey, and found out the switches work perfect and I was getting 12Vdc to the motors. I removed the motors and gearing assembly, and found very heavy corrosion in both motors (see pic). I also opened up the window gearing assembly, and found the grease to basically become a solid material. I scraped as much off as I could without damaging the gearing, and then lubricated both the main gears and the drive worm gear with white lithium grease. Finally, I manually put each window into the up position and configured the winding mechanism to keep them up ( I do not have a manual window tool to crank it up).

Does anyone know what the replacement motor would be in order to replace it? I was going to take it to NAPA or Pep Boys and see if they could match it up, but if anyone knows that would help a lot! Thanks!
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As an update, I have done a LOT of looking and have confirmed that the units were originally made for SPAL, and the motor has a part number of SPAL # 35.90.18. I have found them in a few places ranging from $150-200 each - ouch! If anyone knows of an equivalent or better unit please let me know - I have been through the archives and cant find anything specific.

 

As Dennis said, I did measure it when it was connected but it was only the 5V draw. The motors are corroded and seized solid - the one in the photo is in much better shape than the other unit, and both are locked tight. I will try to dissasseble and clean them to see if I can get them working again, but if not will have to buy new ones. Good news (relatively) is that I found brand new ones for $115 each, so if I have to replace them at least have an option.

I will definately look to install a relay in there to help protect them in the future, and keep them operating fast. My next window challenge will be to get one of the rear windows unstuck....one works great and the other doesnt move, but I do know it gets power and the motor is trying.....will refer to other fchat threads for info on that one....