Questions regarding my 4WD

I will start this question with some info
88 chief
4.0L
5spd with BA 10/5
NP 231 AAC transfer
D30 axles

When I got the jeep several months ago my 4wd worked ( I dug four big holes in the lawn after week of heavy rain)
now I have nothing (got stuck leaving my buddies barn this afternoon)

I will do some searching before I ask any questions regarding why its not engaging(its vac somewhere right?)
The question is though when I put it into 4H an orange Part Time light comes on in the idot cluster, N no change, 4Lo no change
is there and indicator that is not coming on?

thanks in advance Ill keep searching but any help would be appreciated

I think you have a D30 front with the disconnect which may have broken a vacuum line. Check all your lines, especially on the axel itself, for any that came loose, or broke. The plastic gets really brittle after some years and may break if the vehicle hasn't been off road too much.

Mine did the same thing and I ended up replacing all the vacuum lines with a new harness and eventually wnet to the Posi-Lok disconnect. Next is just getting a non-disco D30 and swapping it out.

thanks... I am pretty sure its vac trouble, lines seemed loose especialy the green one(disconect?) but its too cold and dark to screw around with it right now its all gunked up down there too so it all needs a good cleaning
just wondering about the indicators though

just thought I would add and edit here... Im a new mechanic so any help is good help

I send you a pm.

i would start looking at the vacuum lines. i see that problem alot even on chevy blazers. or if you decide you don't want to rely on something as week as airline, you can either convert it to posi-lok (cable actuated), or for a few bucks, convert the passenger side to a new style non-disconnect axle.