Lost 4WD, light just blinks . . .

[captaincrunch]

96/GMC/1500/Ext Cab/Z71/6.5TD

Usually about once a week I go down this gravel road and I've been trying to push 4WD Hi and Low to keep things working well.

Well, last week I did it and the 4WD light only blinks, it never locked up . . .

Is this an electrical thing or mechanical? Where's the best place to start looking?

[More Power]

Do you have a push-button selectable transfer case?

If so, there a re a few reasons why the 4by light would blink (computer not happy with the function of the 4WD system).

Does the transfer case actually shift into 4WD? Does the front axle actually engage?

With a push-button selectable transfer case, 4-Lo won't engage unless the transmission is in Neutral and the vehicle is traveling 3 or less mph.

Let me know,

MP

[captaincrunch]

Yes, it's a push button

No, not engaging at all

Haven't tried to stop/neutral/4w-low yet. will this weekend. (Alt died last night, not driving it today)