4wd problems

[captaincrunch]

96/GMC/1500/Z71/4WD/6.5

Electronic 4wd switch only blinks. Will not go into 4wd.

replaced actuator/wire harness. It does engage but still no 4wd. Fuse was blown, replaced but still no 4wd.

I'm stuck . . . what else is there?

Is there some sort of computer that needs to be reset?

[NH2112]

Did the new fuse blow too? If so then you've either got a dead short in the circuit or the sliding collar/sleeve is stuck and the actuator motor is heating up and blowing the fuse when it tries to go into 4WD.