i'd like to know whats wrong as well...
i picked up a 2005 GXP and it already had the "service vehicle soon" message on the DIC
the original/previous owner had taken in to GM and had spent $600 with them to try and figure it out, and they came up with 0 results, absolutely no other lights are on, and the previous owner mentioned how it normally comes on when driving in the city, but when driving on the highway, it never comes on
when it comes on at low speeds (aka city) i just click the reset button and it goes away for a while
