When I look at your picture, I can see two others wires connected on the other side of battery post which would not be disconnected by battery disconnect. So that is why you still have power to trailer......probably battery ground.....battery disconnect can be on either post, does not make a difference if wired correctly.
2011 Rockwood 8319SS with ProPride 3P hitch/GoodYear Marathons/TST TPMS 507
2008 F250 Lariat CC SB 6.8L V10 4.10 axle ratio (NITTO TERRA GRAPLER G2 LT275/65R20E)
Yamaha 3000iseb generator:Progressive Ind. EMS-HW30C : Eastern Ontario
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