Hey all,

New member here, but looking to diagnose a few issues with my company vehicle. 2008 'burb. Believe it's LT or LTZ model. Just about 87k miles.

Driver side rear window isn't working. I figure it's either a bad motor in the door, or something with a fuse. I've ruled out bad switches considering neither driver's switch or switch in passenger door is getting the window to roll down. Anyone have any idea what else could be causing the issue? Hoping to make this quick and easy fix rather than bring it to the dealer for an expensive diagnosis and repair.

Also, while sitting at idle, the engine seems to be running a little rough. I haven't noticed it actually dropping the RPM needle, seems to happen regardless of A/C running or not. Not sure what could be causing this. Any help is appreciated!

Thanks in advance!

 

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167 views and no one seems to have these issues?
Anyone? Anyone?

 

87K is getting close to needing new spark plugs, if they haven't been changed already. Running some Seafoam through the fuel and brake vacuum line might help if it's an air/fuel thing.

I know the GMT800 trucks had window regulator issues. Have replaced two on my 2001. Not sure if that carried over to the GMT900. My 2008 windows function fast and flawlessly. It can be a bad switch, because if your driver's switch is bad, the window isn't going to operate. I believe they're in series, not parallel.

 

Mine had bad switches in both rear doors that the dealer replaced before I bought it. The windows would go up and down from the driver switch pack though.

If nothing produces a motor sound, and all fuses are good then either all the switch packs are bad or the regulator died. I would the a bad regulator would blow a fuse though. Best way would be to just remove the door panel and check for voltage right at the regulator. If voltage and no movement, then you know the problem.