May I jump in?
I see you are talking about blower relays. I have a problem with my 98 SL500. The blower is stuck on. Even with the key off and out of the ignition. I have to pull the fuse just so my battery will not die. Is there a relay that could be the problem? MB dealer said it was my A/C control module was at fault (over $600) to fix. If there could be a relay to check or change I would rather do that than lay out $600 for nothing.
Thanks for lettin me jump in..