Adding a trickle charge feed to my winch battery has been on my todo list for awhile, and I want to verify the 1 o'clock pin is fused and or has a diode in it before I hook it up to the battery. If its hooked up to the tiny trailer brake battery that's probably a 9 amp hour battery at best I don't think it would require much protection other than the fuse in the fuse block to protect the circuit, but if I hook my 1000 cca battery to this wire and the batterys in the truck are weaker than the trailer battery it could potentially see some huge amperage and hopefully blow said fuse, but if it isn't fused or has a diode its going to melt stuff.
Also I don't want the trailer battery to be weaker than the two truck batteries (that are wired parallel) and inherently cause the alternator to overcharge the two batteries in the truck if the weak trailer battery is "faking" low battery voltage. I think all the correct logic is designed into the 1 o'clock pin but I'm not one to take this forgranted and melt something. Considering the amperage on the small trailer brake batteries may be below the threshold of the wire amperage and consequently the designed in "logic" may be to just run a large enough wire to handle the small battery amperage and not put any other protective logic into the circuitry, which would be the cheaper or more profitable solution if you where a automotive engineer trying to squeeze every cent out of the product. Then when someone puts a high amperage battery on the tail end of the truck without a diode that small LONG wire won't be able to handle the amperage.
I would assume the center pin doesn't have any logic to it at all, but will carry more amperage as its a larger wire than the 1 o'clock pin. So you could wire in a voltage regulator and diode for the ultimate solution, which is sort of my plan, but I might get lazy and just throw a diode in the 1 o'clock pin and hook it up...
Dave
