C-5 Window Roll-up Problem

[GetVette]

Recently, my 2000 6-speed drop top passenger window began acting up. When fully DOWN the window did not roll back up and only gave a subtile control module "plunk" when the window switch was pressed to either up or down.
Two pluks for up, one for down and a small voltage drop in the down position. I removed the door panel and sound abatment covers and with the control module and door switch assembly hanging freely, whacked the door shell 3 times with a rubber hammer where the window motor is mounted. This fixed things for about a week when the problem occurred again. I know the motor works but don't know if the control module is defective or if there is a switch inside of the cable spooler mounted on the motor assembly that cuts power in the fully down position. I would GUESS that the window travels down to the bottom, the power remains at the motor which causes it to get quite warm and then a lockout occurs. Anyone else have this problem and what can be done to fix it without seeing the dealer? Is the control module the sole power control for the motor under these circumstances.
Thanks, BG
2000 6-Speed Drop Top, LS1, Silver, 11,000 miles
1979 Coo-pay L-48, Green, grocery getter. 85,000 miles
1981 Coo-Pay L-48 Silver, almost show quality 40,000 miles
2002 EZ-Go Golf Car, Green, Electric Hybrid Vehicle, 4 miles per volt

 

[schmaltzr]

Sorry, but I've not had this problem thankfully. You might want to purchase the mechanics manual. It answers these kind of questions. I looked in my 2000 manual and the dark blue and brown wires that feed into the Right Hand Door Control module run the window. There doesn't appear to be anything between the RH DCM and the RH window motor. The manual says to look at any system codes on the Driver Information Center (DIC). The BCM should store codes if there is an error. No Driver warning message will be displayed, but the code is stored for your retrieval. Most of the diagnostic procedures require a diagnostic scan tool to tell you how to track down the problem. The manual did say that the DCM is most likely not your problem as they are pretty reliable. I think the DCM detects voltage changes to determine if the window is at the end of its run or not. I do quote from the manual "If the RH window down switch signal circuit is shorted to ground or the RH window down switch is stuck closed the RH window will remain down at all times." so it could be the window switch that is making the motor hot and preventing the window from responding. This is my best guess. I hope it helps

 

[GetVette]

Window sticking problem solution

I hope this information helps others with this frustrating problem.

Following my last post, I tinkered a bit more with my window motor/cable assembly and found the following:
The Door Control Module controls the "window express down" action through two relays embedded in the DCM board and it also controls the window "up" process through one relay. When the window switch is pressed and held for "window up", it activates a N/O relay to apply directional voltage from the DCM to the window motor, bringing the window to a fully up position. When the switch is pressed and released (ONLY ONE TIME) for "express window down", two relays apply directional voltage to the motor continuosly until the window glass and mounting assembly meets the mechanical stop at the bottom of the track. This causes a locked rotor condition and subsequent voltage drop sensed by the DCM (because the motor is still powered) and if (IF) things are all working, the module then cuts power to the window motor after about 3 to 5 seconds of the window bottoming out. In my case, the DCM was functioning correctly but the motor torque for that last 3-5 seconds after hitting bottom was enough to cause the window motor/cable spooler assembly to jam in the fully down position. That is why so many posts on this common problem mention whacking the inner door panel where the motor/spooler assembly is mounted as a quick fix for the non-roll up condition. There are two ways to prevent the motor/spooler from locking up in the window down position. 1. When lowering the window, press the window switch twice (instead of once) and hold the switch down on the second press until the window is down to the desired level, then release. This should take the relays out of the loop and prevent the sticking window at the bottom of the track. 2. If you prefer pressing the window switch only once for express down, immediately press the up or down switch once when the window reaches its fully down position. This will release the relays and keep the window unit functioning properly. I have found this to work every time over the past weeks, despite a continual sticking problem at the bottom prior to invoking the revised operating procedure. Read write-ups on the 2000 Buick LeSabre or Park Avenue, the same problem exists with that GM vehicle.