'96 silverado, 5.0L, auto. Four wheel drive won't engage, 2wd lite flashes then stays on. Have replaced switch in dash and bench tested axle actuator. Just put a new shift motor on T-case, then turned key on ... 4H lit on switch ... pushed 2wd and it shifted to 2wd. Thought I had it fixed, but when I tried shifting back to 4H it blew the T-case fuse (#2). Tried another fuse, no fix. Fuse #24 (FWD) is good. Unplugged both connections to new T-case motor, put power directly to motor and it moves both directions and the driveline seems to be engaged/disengaged accordingly. Is it possible that the T-case is shifting "too hard", thus putting too much load on the shift motor causing the fuse to blow? (it seamed to take a bit of effort to rotate the shift tang with an 8" adjustable wrench.) I'm going to try unplugging the front axle actuator and trying it again.

When the T-case shift motor is engaged the front drive line will not turn by hand, it seems to be engaged ... is this condition correct? or should I be able to turn the drive line thus turning the front wheels as well?
Any other ideas?
Thanks.

What transfer case?

If fuse is blowing you need to find short.

Fuse 24 feeds
Transfer case select button.
Spare power source.
Auxiluiry batter relay if one on it.