Service Four Wheel Drive Message

Just picked up a 2000 burb and about 2 days later the wife said when she was leaving work the message center said to service 4 wheel drive after starting it up. The message isn't there now.

My brother in law has a new Envoy and he had the same message about a week ago and the dealer said they cant find anything unless the message stays on there..

Anyone have the same experiences and or remedies.. I was thinking maybe low fluid levels but I have no clue..

Thanks

The transfer case control module has seen a fault in the 4WD system..most likly electrical...
Most of the ones I have seen needed the Transfer case shift control module replaced (4wd switch on the dash)

Thanks Merlin,

I am taking it back in tomarrow for them to finish some things, so i hope that is all..