ICC unit playing up after reconnecting battery.

[DolphinJames]

First ever thread anyway, I have just recently disconnected the battery (neg- first off, last on), and when I started the car 2 days later only the trip modes and aircon temp settings were showing. No stereo displays or fan and aircon settings displays either. The radio and CD player now do not work. I have a 2005 BA Fairmont with prestige ICC unit. would appreciate it if someone could advise me on what the .... has happened. Excuse the nerves it is my first time.