Hi ED FAIRBANKS. Welcome to the forum. There are a number of potential problems you could run into. Right around 2001 - 2002, GM started this silly nonsense of using computers that are programmed to the vehicle identification number. Their excuse is it was supposed to be a theft deterrent because the computers, (up to 47 of them), could not be used on any other car. What it means for owners is you must buy a new one from the dealer, have them install it, and pay them to program it. The instrument cluster is a very expensive computer.
Simply installing a used computer from the salvage yard may result in it not functioning unless it can be reprogrammed. Also, in rare instances, I've heard about engines not starting after an unrelated computer was replaced. The anti-theft system doesn't like things being tampered with and assumes someone is trying to steal the whole car. I have to admit, I've reprogrammed computers before on Chrysler products, (that was very easy), but I never had to program one to a specific car, so I don't know how much work is involved or what the typical cost is.
Also, be aware that beginning in 2002, GM was dirty enough to build the Body Computer into the radio. If you disconnect the battery, you may need to have the radio reprogrammed at the dealership before any of the other computers will function. If you do attempt to repair your cluster, do not disconnect the battery. The Body Computer is the main unit that all the other computers talk to.
I would suggest finding a used cluster in a salvage yard before you take yours out. You might be able to replace just the housing and brackets without disturbing anything else. It would be especially fine if you could do it without unplugging it, but on most GM products, the plugs are built into the dash and will unplug automatically as soon as the cluster is pulled forward. Be sure the ignition switch stays off when you have the cluster out.
On most cars, once the computers are programmed to that car, they will retain their memory when they are unplugged or the battery is disconnected, so they will work again as soon as they are reinstalled, but it is still best to leave the ignition switch off when any computer is not connected.
Is it possible you could glue the broken mounts? If they are missing, you might be able to cut them off from a used cluster, shape them to fit, and use epoxy to glue them in place. This would avoid any potential electrical issues which would be nice since everything is currently working.
Saturday, May 22nd, 2010 AT 3:10 PM