'88 Passenger window does not go down on it's own.

[THEMCGUIRE]

My passenger window will not go down on it's own.

If I pull down on the sash channel with a LOT of fingertip pressure for the first 8 inches or so while pressing on the down side of the switch it does go down.

After 8" the motor takes over with just the switch and it goes down the rest of the way. It goes up easy and fast now that I put the relay's in.

The glass broke due to welding slag. Since then I have done the following to both the driver (which works fine) and passenger windows:

1. Replaced the glass
2. Replaced the door glass run and door window seals (inner is installed, outer not yet installed)
3. Saturated the door glass run with silicon
4. Lubed the channels and rollers and regulator's with lithium grease
5. Replaced the motor
6. Added relays to operate the windows.
7. Tried loosening the run channel bolts to let it float free so there was no pressure on the glass.
8. Pulled regulators from both sides and compared them. They appear to be aligned the same. I do not believe that passenger regulator is bent in any way.

Anyone have any ideas what is binding it for those 1st 8 inch's ?

 

[nitro_rat]

Contacts bad in the down side of the switch? Current has flowed long enough after the 8" you held it to continue the rest of the way down?

It sounds like you have replaced everything. All the usual suspects anyway. Same problem though. Got to be something you haven't changed. Bear in mind current must first travel through the drivers door switch before it gets to the passenger side. Your gremlin might be hiding in the other door.

Happy hunting!

 

[THEMCGUIRE]

1st off, thanks so much for taking the time to respond to this post.

I have new switch's on the driver side, I "LOST" the old ones, long story.

The driver side switch for the pass side works just like the pass side switch, i.e. problem is identical with both switches.

The passenger side switch's are original. I also installed relays for both doors. So the power is only needed to operate the relay.

I have 12v where it connects to the new relay on the pass side when operating the pass switch, you can clearly hear the relay click when you operate the switch, in either direction.

FYI. I have to operate the down switch or it will not go down at all, physical help from me or not so the switch must be doing something, right ?

it is so strange, how easily and fast the window goes up but not down. I guess I will try and replace the pass switch next.

'

 

[nitro_rat]

FYI. I have to operate the down switch or it will not go down at all, physical help from me or not so the switch must be doing something, right ?

Yes, that's why your problem is so odd. The plastic tape usually "strips" and causes the window to need "help." In this case, the switch does nothing until you "help" the glass to a good part of the tape. (Obviously you know how this works, hoping to help somebody else.)

I'm afraid your tape is going to strip if this problem persists. Then you'll need a new regulator. Have you inspected your tape? Maybe it's half-stripped for a ways at the top? At this point I might be inclined to try another regulator.

 

[Irish1941]

Yes, that's why your problem is so odd. The plastic tape usually "strips" and causes the window to need "help." In this case, the switch does nothing until you "help" the glass to a good part of the tape. (Obviously you know how this works, hoping to help somebody else.)

I'm afraid your tape is going to strip if this problem persists. Then you'll need a new regulator. Have you inspected your tape? Maybe it's half-stripped for a ways at the top? At this point I might be inclined to try another regulator.

Tape?
I'm right in the middle of rebuilding another pair doors and there is no drive tape in there. Regulator gear is driven right from the motor.
The gears can strip but it makes a lot of noise. You'll know stripped gears when you hear it and you would have seen the bad teeth when you did the motor. Plus motor would be spinning until it hit good section of gear teeth so you can rule out bad gears.

And I'm pretty sure it's not an electrical (switch) problem esp since you did relays and does same thing with either LH or RH switch.
Motor is working, glass is just stuck. Easy way to check is open the door and watch the interior light when you hit down on the switch when its all the way up. Lamp should noticeably dim. Dimming light = motor working, drawing power.

When you help it down, watch the front channel at the vent window. The window rides in the front channel all the way down and if the vent isn't completely in it will bind the glass. And make sure that 5/16" screw right below the vent is installed as well. Make sure channel is all the way in as well.
Another thing is that new channel tends to grip the glass as it goes down.
I'd pull the front & rear channels out one at a time and run it up and down before I'd start replacing the regulator.
Problems like this is hard to help without it being in front of you but from doors I've done, it's almost always the vent window that causes problems.
Power regulator for '81-'91 Blazer/Sub. No drive tape.

 

[nitro_rat]

I'd have sworn the last door I was into had the drive tape. Must have been something else!