GMC Repair: 98 Sonoma 4wd blowing ATC fuse, tccm, wire harness

Question
have a 98 Sonoma 4wd 6 cyl vortec engine with push button 4wd switch. I keep blowing the ATC fuse under the hood. I replaced the fuse but it blew again.  Any help would be greatly appreciated.

Answer
Hi
It REALLY depends on which Transfer case you have (RPO code NP1 [2 speed selectable]) or (RPO code NP4 [one button Automatic])
Looks like it is either the Encoder motor (that fuse feeds the motor on both systems) the TCCM (if the NP1) or ANY of the related wire harness containing CKT 1640 the orange feed circuit from the fuse.
I Hope this helps.
Good luck
Pawl