clkrac3r

Whenever the car is off and the key is removed, i can open my trunk. But when i do, the radiator fans starts to run at full speed and the instrument panel(all dash lights) and trunk light start flashing. When the car is on and the trunk is opened the light in the trunk flashes and a light defective warning comes up as a malfunction. And last of all, when the headlights and running lights are off the third break light works, but when the lights are switched on the center break light doesn't turn on and the license plate lights don't work either. I've checked all the lights on the car and they all check out correctly. I need Help.

84k miles
CLk 320 - 2000
Cabriolet