I have one of these TEST ADAPTERS in my tool box to plug into the 7-WAy TRAILER CONNECTOR on the truck. This adapter has LED LIGHTS for each of the OUTPUTS coming from the truck side. If it doesn't work here then you know the problem is on the truck side. A great tool to have when having problems.
I got mine from ETRAILER but see them on AMAZON and I imagine some may available at auto parts stores.
ETRAILER.com has a lot of information including diagrams on their web site for everything trailer. Good place to go for info...
I am not aware of any fuses on the trailer side for any of the SAFETY lights or functions. I have found some WD40 sprayed into the 7-way socket before I plug into it helps some keeping the blades clean.
My truck does have fuses in one of the DC FUSE PANELs for the 7-way trailer connector. Also the key ignition has to be on for some of them as well...
I am just assuming the truck side connections for TRUCK CAMPERs are the same as used with RV Trailers here...
Roy Ken
