2002 Service 4-Wheel Drive

Hello I'm new and found this site researching a problem.
My truck 's check 4-Wheel drive light came on tonight and as I was driving home kept jumping into 4AWD or 4wheel high, I would switch it back and it would happen again after awhile.
The 4 wheel drive still works and I can engage and unengaged it.

The manual isn't much help it just says take the vehicle in to prevent a serious problem, is the truck safe to drive, I'm not sure when I can take it to get looked at?
thanks.

There is a TSB out there for the 4wd control unit. It probably needs a computer update.

Yes, you either need a transfer case computer upgrade/reflash or if it gets worse, perhaps a new computer. They unfortunately can go bad have been fairly common to fail.

Yes, you either need a transfer case computer upgrade/reflash or if it gets worse, perhaps a new computer. They unfortunately can go bad have been fairly common to fail.Yeah mines been switching here and there the past couple of weeks. This happened when I first bought it about 8 months ago, and I had it reflashed then. Now it's somewhat back. I really don't want to replace the computer