99 Yukon - 4wd won't work, blown fuse

Greetings all,

I've got a 99 Yukon 5.7. I noticed the other day that the 2wd/4wd selector switch lights were out. Found fuse 24 blown. Replaced it, and it blew again on start-up. I unplugged the 4wd actuator on the transfer case - same results. I unplugged the selector switches - same results. I've got continuity between the fuse 24 output and ground with the switches and actuator unplugged - so it seems like I may have a short...but I'm not certain since I don't know what else the wire feeds (not covered in the schematics of my Haynes manual). I've traced the wires from the actuator and the switches as far as I can, and found no obvious signs of wear or stress. Anyone have any suggestions?

Thanks in advance, -Dave.

Hey Dave,
I came here looking for a solution to your exact problem, only difference is my truck is a 95. No posts here, but since it has been almost 2 months since your post was wondering if you found a solution elsewhere? If so I would really appreciate knowing what the answer is.

Regards,
triguy78

Hey guys, I too have a 95 Yukon that the 4 wheel drive doesn't work. Fuse 24 blows when I put it in 4 wheel. I would love to know if you hear about a solution.

don't know if will help but you know there is an acuator on the front diff as well

its the acuator in the front differential. its about 99 dollars at orielly's, its very easy to change out, just un hook the wires and un screw it. replace the fuse and screw in the actuator and plug it in. get in the truck put it in 4hi. if the fuse doesn't pop then you shuld be good if it pops again look into the either the push button 4x4 or if its on the floor check that as a well

the actuator is heat activated so the short could be in the internals of the actuator. have you replaced it to see if that helps? if you have a buddy with a 96 and up yukon, tahoe, or a half ton z71, just pull theirs out and put it in yours to see if that fixes your problem. good luck