So when I bought my blazer (2000 LT) I noticed that the drivers power window was not working. And while driving at night none of the lights lit up on the window switch. So it seemed pretty obvious to me that it was the window switch. So I ordered a used one off ebay. Got it home put it in and it still did not work. So I decided to give up for the night. Woke up in the morning and just for the heck of it I tried the window again and suddenly it worked! Yay for me right? Oh no 2 days later it stops working again. I know the switch is ok so I tore the door panel off today and no problems with the wiring or anything like that. So my question is....... is this something that the window motor itself could be doing? Or is there someplace else I should look? All the other windows work by the way.

 

I changed the window motor and that cured my problems that were like that, I got mine off eBay for 25 bucks, lifetime warranty, it works great now. Did you check the wiring to make sure the plugs are seated correctly on the motor and switch?


Does it go down some then stop?

 

With the door panel off and the key on, use a test light and probe the wiring for the window motor. Push the switch to roll the window up, one wire should light up the test light, the other should be grounded. Push the switch down and power should be reversed. Meaning the ground should now light up, and the other wire should be grounded.

 

If the lights aren't lit, except for when it works, then you have an intermittent connection problem. I have seen quite a few GM vehicles with an intermittent connection at the plug into the back of the master switch. If you move the plug around and find that you get, then lose power, it's the connection. Sometimes I have been able to remove the wire connectors from the plastic and re-bend the contacts to give them better bite, but some times I just had to put some tension on the wiring harness in a different direction to keep it fully connected.