Because my german is really bad, I hope it is ok that I write in english. I read german just fine so please reply in german. From the schaltplan that Georg sent me, I understand that there are three temperature sensors. Two inside the car and one outside. Apparently the steuergerät calculates the amount of heat that is needed comparing the outside temperature with the inside temperature. The amount of heat is regulated with an airvalve that mixes cold air with hot air. Now my question: when the klima is switched on, the incoming air is much cooler. As far as I can tell from the schaltplan, the steuergerät doesn't "know" when the klima is on and therefore does not compensate with more heat. Is this correct? The result in my car is that the temperature drops about 4 degrees when I turn on the klima. This doesn't seem right. Maybe I expect too much of the system? Thanks for the answer on the blue PLC... I have the same problem with the relais and need to replace it. (The relais seems pretty light for the job it has to do.)
