My Service 4WD came on in my DIC, by the time I got it to the Dealer it had went out. When it first came on I did like the owners manual said, I pulled over and shut down the engine and then restarted it. The Service 4Wd came righ back on. The next morning when I took it in to the dealership it didn't come on. The Tech checked for codes and didn't find anything. They said the flashed a updated program to the Transmission. It hasn't came on since.