2004 Chevy Avalanche 4 wheel drive

I had a problem recently during a snow storm I selected 4 H on the 4 wheels drive selector. It started blinking and said service 4 wheel drive system needs service on the message center.
it would not go into 4 wheel drive

I used a scan tool an no error codes were present.
i tried to select 4h with scaner connected and again no codes were present

im able to put the truck into 4 low.
any ideas.I dont go into 4 wheel drive much. Maybe 6 times a year. Of course this year we have 3 big snow storms and the 4 high fails.