Hello,

I am trying to figure out why the window on my 2008 Hummer H2 is not working. I was able to connect a spare window regulator to it and the spare didn't work. I have been combing through the fuse boxes and relay to try and find something that is out of place or blown and I am at a loss as to whether nothing is wrong with the fuses or I am overlooking something. Does anyone have any suggestions on how i should troubleshoot this?

 

Also, the other electronics on the door seem to work. The other windows work and the regulators for the rear passenger window were not trying to turn on at all as if they weren't getting any power at all.

 

This might help.... service docs pdf.

 

Assuming this is a rear Window?

By "spare window regulator" is this a rear Window Switch or Front Door Module?

You may already have a schematic, anyway here is an '04' diagram which may be similar and may help.

If it suddenly stopped working it could be a break in the door wiring e.g. check the grounds G302 or G306 depending which side it is.

A some history and details could help resolve this, please keep us posted either way 👍

 

yes, the rear passenger side window. I just bought the hummer from an auction and it was missing the door panel for that door. When I purchased the door panel the shipper was willing to send the window regulator to which happily I agreed. To test the spare regulator I just plugged in the connector and tried the switch from the driver door, then I plugged in the switch on the door panel and tried that as well which didn't work. I assume before the previous owner lost possession of the vehicle, he was trying to troubleshoot the window.

 

Ah there's passengers both sides at the rear, but I know what you mean, there are also right-hand-drive Hummers.

This is what show up for the "Window Regulator & Motor Assembly"



So here is the order of checks I would be tempted to make:-
1, GROUND - Check the ground going to Window Switch terminal "E" via G306 to the chassis.

2, With the Ignition ON, unplug the motor, operate the window switch Up or Down and measure the voltage at the harness end of the connector, it should be around 12V (VBAT) Change switch direction and check the polarity reverses. If you have 12V in both cases then it is likely to the motor regulator itself. I would like to say measure the resistance of the motor, but I suspect the regulator contains active components which limit the motor current, similar to the power mirror arm motor, so a valid reading may not be possible.

3, MOTOR DRIVE POWER - If there is no 12V at the motor connector, check terminal "A" this should be +12V always. If not, and the right front window operates, there must be a break in the wiring.

4, LOCK-OUT POWER - Again with the ignition ON check there is +12V on terminal "D" (window LOCK off) If not, there's it either a break in the wiring or a problem with the BCU itself (Pin A6) There is a caveat here, either the relay diodes are shown the "wrong way round" or the window switch is shown incorrectly which could change things.

It could be the BCU as you will have probably checked most everything else but hopefully not.

 

The wiring harness under the driver seat gets pulled every time the seat changes position. Eventually it snapped one of the dozens of wires in it. (Dealer then simply jumped that one broken wire around the harness, faster than easier than replacing connector or pulling all wires out of it.)

That one wire caused many things in the car doors to stop working. Like passenger side window, etc. I was chasing all sorts of electrical issues, and it came down to one wire, which apparently was common to more than 1 circuit.

Long shot that it has anything to do with it, but you may want to trace some wires for continuity.
Please update us with the verdict.