Looking for help please. My Ml 350 has been to the MB dealership 3 times for a problem blowing the F5 fuse. It controls the AC and instrument cluster. The first they said they replaced a connector block?? for about $500. I took it back 6 months later and they tried to charge me again. It has worked since May this year. Now this morning it has blown again. I would like to fix this once and for all. Any help would be greatly appreciated. Thanks in advance.

Anybody have any ideas?