I think I earned it this time around. So I've been troubleshooting vacuum related HVAC and 4WD issues on my truck for a while now. Finally ended up replacing a bunch of vac lines under the hood, check valve, vac ball, etc. Got good vacuum everywhere, HVAC vents now working, still no 4WD. Pull the battery tray and the 4WD actuator shreds when I touch it. Replace the actuator and all is good.

But now the electronics for 4WD aren't working . Truck is stuck in 4Hi and lights just flash when I try to switch anything. Do more research and decide to swap out the TCCM and selector switch in case one of them is bad. Do that today (in my truck TCCM is behind ash tray so a lot more kick panel parts to take out) and the symptoms are the SAME. WTF! I had already tried the DTC port jumper to get any codes and there weren't any. But I decide to pull the 4WD fuse and do the clear memory thing. Lo and behold, the fuse is blown!

Replace the fuse and we're golden. Like I said idiot of the week. Now to see if the ebay place bought the TCCM from will take it back. Or I'll just list it myself.

Weird that the selector switch worked at all with a blown fuse but whatever.

 

I would keep the tccm just so you have a spare. Also I have done simular things. For example I have a diffrent hood that I put on for when I go on my offroad trips beacuse I have a snorkle. So the last time I put the hood on I forgot to reconnect a ground for the windsheild wipers. And I than proceded to take the wiper circut board out and resoderd everything. So 2 hours later I am just about to get a new wiper moter when I find the ground and I proceed to feel stupid for the next 3 hrs.