I bought a Blazer last week and the windows don't roll up and down, Today I took off the door panel to see what the problem was and on the drivers side the motor has been replaced but when I click the up or down button the motor just shakes.. I pushed the window down and when I pressed the down button the window started going down. The regulator gear looking thing looked pretty damaged and grinded down and im thinking that is the issue and I need to get a new regulator for the drivers side. On the passenger side it looks untouched and nothing happens when I press the up or down switch so im assuming that that is just the motor that is broken... Any one have a better idea than me? Thanks for the help

 

A volt ohm meter will tell you if it's the motor or the switch. The instructions will tell you how to test each component. It's worth buying to save some expensive guessing.

 

Would the drivers side motor fit in the passenger side? I could just plug it in to see if its the motor or switch and if it fits i could just buy the motor and regulator for the driver side to save money

 

A test light would be even cheaper than a meter. If you have an extra 12 volt bulb out of something you could make one. Test the plug at the motor while pressing the switch, no light, then test the plug at the switch.

 

So i changed the drivers regulator and it works, I also changed the passenger side motor and it works but now when i press both buttons to open the window closes and when i press close the window opens, do you know why this would happen? Im thinking that its just the two wires going into the motor switched around ?

 

That would be where I would look. I believe the plug to the switches only goes on one way. Glad to hear you got them working.