Always live circuit
 

We have a 2012 Mini Cooper 6 speed hardtop that we tow behind our motor home. Needing an always live power source for the auxiliary brake, I tapped fuse #16, courtesy lights, and mounted a 12v receptacle only to discover that the power from that fuse goes off after 30 minutes when the ignition is off. What's up with that? Is there another fuse I can tap or should I just run a hot lead straight from the battery?

Thanks in advance for any assistance..

Rick