Chevrolet Repair: Display problem, pontiac trans sport, digital displays

Question
I have a 1998 Pontiac Trans Sport Montana mini-van.
I replaced the display that is located in the ceiling console. This display shows outside temp, compass and MPG. I used a brand new unit. It powers on, but it only displays a "C" on all of the functions. I assume this means calibrate? Is there any way I can calibrate myself without a visit to the dealer?
Thank you very much!  

Answer
im not sure if you can calibrate it all by yourself. by the way, im pretty sure youre right about the c. digital displays like that normally read c, or cal. now, im pretty sure you can calibrate the compass yourself, but i dont know if the rest will fall into place after that. you have to do three consecutive circles, i think counter clockwise. all the circles have to be done at one time. like i said, i dont know if the rest will fall in place, but try it, they might. if not, youll have to take it to a dealer.