Rear window won’t go up

[TPCLARK]

I’m working on my 1990 K5 with the powered rear window. I’m having an issue where the switch will roll the window down, but not back up. When I checked the cable I could turn it and roll the arms up, but as soon as I hook it up again it won’t roll up only down. Is it a switch issue? Or is the regulator thingy the cable goes to going bad. Has anyone experienced this issue?

 

[swettysblazer]

CHeck the safety switch on the drivers side of the tailgate. If it isnt closed all the way it wont allow the window to roll up .

 

[Blue85]

Check the safety switch on the driver's side of the tailgate. If it isn't closed all the way, it won't allow the window to roll up.

Yes, the safety switch is the most common cause of this problem. They can be removed, disassembled, cleaned and reassembled, often fixing the problem. You can test it by putting a jumper wire on the connector. Some people actually call this a fix, but it's at least good for troubleshooting.

But for sure, verify the problem is there with both the tailgate keyswitch and the dash switch. That tailgate switch is notorious for failing contacts.

 

[rampage]

In case it’s not clear, you need to remove the latch on the drivers side of the tailgate to get to the switch. It’s on the latch when you pull it out.

 

[esva_rig]

Agreed with above, the switch is the likely culprit and probably the easier fix too. I had some other issues on mine I just went through however. The truck has been sitting for quite a while, and the motor was seized (water leaking in through the back glass seal). I found this reman at summit, and it looked and worked great. Not cheap, but I was having some trouble finding them:

Pardon Our Interruption

www.summitracing.com

My rear key switch also wasn't working, but I don't think that had been for quite some time even before I bought the truck (I took it apart and the main contact strip had basically disintegrated). I found this guy's shop where you can buy a whole new matching lock set:

LockSets

My dash switch was a little corroded, but a few shots of contact cleaner, some manual exercising, and some dielectric grease and she was working good as new.

While I had my tailgate all apart, I took the opportunity to clean and regrease the gear box and regulator, which did help with the speed and ease of movement.

Those few things and chasing out a few gremlins in the old wiring, and she works good as new.

 

[RDurost]

Agreed with above, the switch is the likely culprit and probably the easier fix too. I had some other issues on mine I just went through however. The truck has been sitting for quite a while, and the motor was seized (water leaking in through the back glass seal). I found this reman at summit, and it looked and worked great. Not cheap, but I was having some trouble finding them:

Pardon Our Interruption

www.summitracing.com

My rear key switch also wasn't working, but I don't think that had been for quite some time even before I bought the truck (I took it apart and the main contact strip had basically disintegrated). I found this guy's shop where you can buy a whole new matching lock set:

LockSets

My dash switch was a little corroded, but a few shots of contact cleaner, some manual exercising, and some dielectric grease and she was working good as new.

While I had my tailgate all apart, I took the opportunity to clean and regrease the gear box and regulator, which did help with the speed and ease of movement.

Those few things and chasing out a few gremlins in the old wiring, and she works good as new.

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