Help, saab flashes like Christmas tree

Hello everyone here, I bought a Saab 9000 CS Schrägheck (150 HP ) Softturbo used 3 weeks ago. Since I almost always drove only BMW, but always the Swede was angry, I decided this time for this. When buying everything was fine. They already told me that the rubber manscrews of the drive were torn in the front, but otherwise everything was fine. Two weeks ago I drove a longer distance with the car and then came in rain. the first hook… the light didn’t turn off, although I switched the light switch back and forth several times. After a good 10 minutes and switching back and forth again. finally the light was switched off. Since the day before yesterday, however, where it was so warm, he began to shine in the operating element like a Christmas room. In the vehicle display all 4 red lights on from the lighting…and further the warning lights of the wash basins, the attached handpiece. Then I looked, the lights are all burning, washing water is full and also brake fluid he has not lost. Therefore my question…has someone ever experienced this phenomenon at his Saab and if yes…what was it? Otherwise, the car itself is a very nice vehicle….is really comparable to a BMW 5…yes..if this warning system weren’t there. I already suspected that maybe a control board is defective. ..but I don’t know about this vehicle yet. Furthermore… when I was driving on the highway for a long time…is the 2.0 Ltr Turbo with 150 hp…but I managed with it only after a long swing the 200 km/h, then it was over. The air filter is still fine, after that I already looked. Maybe someone can give me some detailed information, if this car is a cuckoo… is BJ 96… and now has 168,000 km away. or whether this is normal. I would like to thank you in advance for your answers. Greetings of the newcomer