BMW Repair: heater motor final stage resistor, aluminum heat sink, heater fan

Question
I read your Aug 9 response on the heater fan final stage resistor. I think I have this problem. I have a 2002 E39 535iT. AC motor does not come on although the compressor does.

If I have the old style final stage resistor, can I replace it with the new type with the aluminum heat sink? Will the parts guys at BMW know what I'm talking about?

thanks so much

Answer
Gustavo, If your parts guys are worth their salt they will give you the updated part. I don't even think you can get the old cast iron style anymore. This is most likely the problem with the symptom you describe. Check the post I gave to 'Wolfgang' aroung 8/24/06 for instruction. This job is fairly easy.
-Evan