Hi, my fellow r53/r50 owners. I have this weird issue and would need your help. My 2004 mcs cooling fan works as it should be, i.e turns on at low speed and turns off after the engine cools down. However, once the ac is on, the cooling fan won't turn off even I turn off the ac. I can see the compressor turns on and turns off when I turn on and turn off the ac. I have switched out all the related relays but problem still persists. I am wondering what could be the problem?

 

Mine does this too. I never really cared enough to look into the cause. I suspect it's a software bug in the DME because it's responsible for controlling the AC and the fan.

 

Hi, thanks for replying, glad to hear that this is kind of "normal" for our car. I freaked out when that happene, lol