98 Blaser no vacuume to 4x4 diaphram

I have a 98 blaser, this winter I lost 4wheel drive. After a lot of investigating my problem was the transfer case control module (which no one sugested in any threads).
Well it didn't snow for a month after I fixed it, well as fate would have it, finally snowed and no 4x4. Now I think the problem is something else, I am not getting any Vacuum at the diaphram. I haven't gotten underneath it yet, but ziptied to the transmission dipstick is what I think is a vac line with a plug on top this also seemes to have no vac to it, is this the test site for vac pressure or is this the vent? Could you help me with the steps to check vac pressure and things to check. Thank you. Randy

That should be the trans vent line on the trans fill tube.
The vac line taps off the intake port that the PCV comes off.
Has a check valve in the line and also goes to a reservior can in the drivers side fender behind the ABS - that line is almost always rotten and cracked.
Buy some vac line I think its 5/16 for the small and 7/16 larger.
The 4wd actuator is under the battery. On 99 up there is also an additional electric solenoid on the fire wall that the vac lines go thru.