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The 12volt pin on the 7 pin connector (2019 f350) is no longer supplying 12V. I looked in the owners manual to find the fuse Location but couldn’t find it. I did see the location for a 12v relay but not a fuse. Can anyone help me with this? My truck is a diesel but I’m thinking fuse location would be the same either way.
I have a 2018 F450, books says #27 in the engine compartment should be the 30A for 12v trailer but its empty on mine. It is only used if you DO NOT have the factory trailer brake controller; I say that because I have the factory controller and this spot is empty. #37 is "trailer tow battery charge relay non-trailer brake controller. #54 is 30A Trailer Brake Control Module, so this one may be blown. I believe this is where the 12v battery comes from when you have the factory brake controller.
Interesting. My truck has the internal brake controller. All the trailer functions work: running lights, turns, brakes, brake lights. I only noticed this 12v issue when installing a lithium battery/ power electronics upgrade in my trailer. Maybe this never worked as i expected. I have solar panels on my trailer. That’s probably what charged my batteries all along when I was on the road. I might need to run a separate fused line from the battery if I want to make use of the dc/dc charger I installed.