yup, another thread on selflevel suspension inactive
 

Hello guys,
my X, is a 2000 4.4i, and for the past year, I would get the dreaded Selflevel suspension inactive every now and then, weeks would go by, and not get it, or sometimes 2 o3 three times in a week, but for the past week, it's on all the time, I have tried to look up info, but most I've found send you to the dealer, I did see in realoem, that there's an air supply control modules, 'bout $120, but don't really know if I should buy it.
my X has 147K miles on it. I do not notice driveability issues, but that sign on the dash pisses me off!
Thanks!

Odds are 10 to 1 it is just the relay for the pump. It is in the metal dome over the spare tire with the compressor. Just swap out that relay, #9 in this link.

RealOEM.com * BMW E53 X5 4.4i LEVELL.DEVICE, AIR SPRING AND CTRL UNIT

Thank you Weasel, if I understand correctly, it's INSIDE that dome looking thing, right?
Thanks,
M.

Yes, just unbolt the dome thing from the triangle of metal braces over the battery and turn it over.