I have a "snag" with my late '99 M5, the climate control sort of works but to get a half stable temp you have to set it at 30 odd degrees C. I took it to my local BMW dealer who pluged it into the box of tricks and came out with a fault code "cabin temp sensor", The parts department cant supply a sender for a M5 without replacing the whole climate control unit "£450 for the bit + coding". Intresting enough they will supply just the sender for any other 5 series 540 etc. Is the 540 climate control different to an M5?? Has anyone replaced the sender one its own??