Monday, June 8, 2009

Auto Repair Adventure #20 - Bonneville Rear Window Fix

About 2 months ago, the rear window on my 2002 Pontiac Bonneville fell down, and wouldn't go back up. A quick search on the internet revealed many of these different Pontiac's are prone to have the windows 'break' off the plastic mechanism inside the door and require a $300 fix. Some people report this 'break' happening frequently on the same repaired car. Great... just what you like to hear. Poor engineering is just as good a reason as financial or economic woes for GM to go bankrupt... anyway, for 2 months now I've tried to keep the window up with duct tape. Yuk.

This weekend we tore into the door to fix it. I always hesitate working on the panelling - too many fasteners that can break or crack. This time, the panel removal went smoothly - just needed a long pry-bar to fit in by each of the fasteners. Popped right off. Not even a single screw holding the panel to the door.

Here is the window mechanism inside the door. Tough to get at. The cable that pulls the window up had broken off the bracket. The motor worked, but did not pull the window up.

This interesting PCB was labelled "rear door module". Just had to open it up and peek inside for a future 'modification'. A couple of relays, and easy attachment points. Not sure yet about the silver heatsink'ed device...

Anywho... after fiddling with the mechanism, it was apparent that installing a new plastic bracket would take a while, if even possible at all. Cost was at least $40 and a days wait, too. So... since it was a rear window, and not that important to my commute, I chose the low-cost alternative. I cut a 1x2" slat to a length of 22.5" long, and put a 1/2" slot into the top of it. Note - usually I get bloody knuckles during car repair... this time it was from the hand-saw doing a quick cut on the lumber, so it doesn't count.

I carefully inserted the wood into the door, and shoved it tightly under the window mechanism and slide. The slot in the top of the wood fit perfectly in under the metal bracket on the window's slide. I then bolted the wood to the frame and metal slide. Now the wood keeps the window up and tightly closed. Done! Best part is that this 'fix' won't break 3 months from now, requiring a repeat repair. "Fixed it right the first time!"

The other 'bonus' is that I don't need the window motor in the door... so I taped off the connector and pulled the motor and pulley! I've been wanting to play with a strong 12V electric motor for other projects anyway... score!

Glad to have this done. On to the next repair...