I have a '94 1500 with the 4L80E tranny. I had it rebuilt 3 weeks ago and tried the 4 wheel drive yesterday for the first time when we got some snow. It does not engage. It has the stepper motor actuator upgrade installed for about 6 years now and has always worked great, even when shifting into 4 wheel on the fly. The transfer case is shifting and locks the driveshaft up. Checked the 4 wheel drive 25 amp fuse and it was blown. I replaced the fuse and still no power to the actuator. Checked at the transfer case connector and no power to any of the wires there either. Rechecked the fuse and it was fine. Called the guy who rebuilt the tranny and he said the four wheel worked when he test drove it (the light has never worked in the 7 years I have owned the truck). I am guessing he is not telling the truth as I know his buddy who is the one who pulled and reinstalled the tranny told me he test drove the truck when I picked it up. Anyway I think maybe during installation something got disconnected or wires got cut. Guess you get what you pay for. It was very cheep at $1100 so I guess I can spend some of my time on it as these guys have washed their hands of it. I need some ideas of where and what to look for. What could have blown the fuse and why didn't it blow again if the problem is still there? Where does the power come from that goes to the transfer case? Is there a second fuse somewhere that could be blown? Any ideas of what to look for would be very helpful.