My wipers, washers, chime, and interior dome light stopped working and from an earlier post someone claimed that the problem was the GEM module. That person also said that it was located on the back of the interior fuse block. In trying to get at the GEM module (if it is behind the fuse block) I had just about had the fuse block removed except for detaching the two wiring harnesses from behind the block. I had succeeded in loosening the harnesses but I could not get them to detach. Can someone tell me if I am on the right track and if I am can you let me know how to get those harnesses separated and any other details that might pertain to replacing the GEM module? I am running out of Rain-X.
Yes you're on the right track. Did you remove the whole trim panel under the steering column? That makes it easier. I've also seen guys disconnect the clutch and brake pushrods too so the pedals are out of the way. The harnesses can be a real pain to disconnect. The ones on the side nearest the park brake pedal can usually be removed from the side with a long screwdriver. The ones at the back just have to be fought with. Make sure you check to see if there was any water in the fuse box of in the GEM. Usually the windshield leaks and the water drips on them.
Once you get the fuse box/GEM out there are just 4 screws that hold the GEM to the fusebox.
Thanks for the advise. I guess I didn't wrestle long enough with the harnesses. I'll give it another try.
When I get the old GEM out do I just need to bolt a new one in place and thats all or do I have to download the data from the old GEM into the new one? (don't know how in the hell I would do that) I thought I read something about this downloading business from a post I read sometime ago.
Actually the GEM you're replacing might only be a CTM...central timer module. Looks the same a GEM....which one you have depends on options on the truck. Some GEMs have programable parameters for the tire size etc but some dont. Depends on the options on the truck. If you have to do any programming you'll have to take it to your dealer. Make sure that the GEM you install is the right one...you can go by the part number on it. Not just any old one will work in any truck.