My original computer functions were very basic (mpg, avg speed, miles left) as I did not get the more advanced package that was an option. The result is that when the OEM radio was removed, these same computer functions are all still working. I can't tell you why other then to surmise that the "brain" is located somewhere other then in the OEM radio.

My installer did not tell me that he did anything special. He did, however, tell me going into the install that I would loose these functions. I'm glad he was wrong.