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I have a 2009 2500HD GMC Sierra. All power windows are inop from the driver's switch. They also won’t operate from their perspective door switches. The passenger window will operate as normal from the passenger switch. Driver had replaced the driver window switch. Looking at the wiring schematic all windows besides the passenger are logic based. I have verified that all the window motors are operating by sending independent power through the wiring harness by back probing the switches at the induvial doors. The switches have power & ground. Truck has no blown fuses. The body controller has power. Using my scan tool, I cannot command the windows nor can I see the switches change state while looking at data display. My tool also wont talk to the driver’s door module or passenger door module but it does say that it isn’t supported on all vehicles. Im thinking that the BCM has failed but I don’t know an effective test to check.
I’d double check as the BCM will most likely need to be programmed in.
You can bypass the switch, BCM and put power to the window regulator motor or motors and test then that way whether with a fused wire, power probe. test light, etc… I hope this of some help for you.
The reason I mentioned sps is I just did a 2011 tdm (theft deterrent module) replacement with a used one from a salvage yard for a customer who’d bought a auction truck that was a theft recovery. The donor truck was a 2007 GMC Sierra aka a GM product. Look on the white label of the BCM and if there’s a line with a arrow on each end of it then it’ll need to be programmed into the vehicle.
Let us know how it goes if you would please. Also any capable aftermarket shop should be able to program the BCM with the proper calibration files so it works correctly.
You might need to check the low speed bus comb connection connector (has green wires going into it and a cap on the plug. Hangs down by the bcm I think the low speed bus may be effected causing your issue. Pull comb out of connector and then try the individual door window switches. Then check using a scope for low speed bus communication at a pin and then jumper each connection in till you find the one that makes coms bad or looks worse than the others.
Hope this helps you. I found an open in this splice pack under drive side left side. This is the low speed communication bus to pcm sending signal to open or close windows. I know you checked power and ground but please verify good solid ground at driver master switch and solid battery voltage before you replace Bcm also get a labscope on th DArk green wire low speed com bus and make sure square wave signal is going out to Bcm before you replace Bcm
This system relies heavily on com bus low speed signal to pcm from both driver and passenger master switches. Hope that helps but if you have good power and ground on master switch on driver side and no low speed com bus out of that dark green wire pin 9 at master window switch. I would go towards a master switch first
Yeah absolutely what Cheryl said here, there has got to be an open circuit in the wire more then likely a ground since nothing seems to work or the low speed Dark green wire is open in that rubber boot harness in the door
