Attaching my 25 pin connector

Hello All. First off, I don’t think I thanked Scott for his answer to my previous question. If not, here’s a belated thanks.
My question is; is it possible to connect my 5th wheels 25 pin connector to my bluetti 200 max so that I can turn on the running lights on the 5th wheel (rather than connecting to my truck)? If so, what kind of adaptor would I need. Thanks, john

Never heard of a 25 pin 5th wheel trailer connector but if you are referring to the electrical cable from the trailer that you connect to the tow vehicle…

You would need to make your own cable by purchasing the female socket that the tow vehicle has and connecting a wire to the socket terminal for the running lights and wire to the ground (2 wires) the other end of those two wires would have to be connected to the high amp DC output cable from the aviation DC output port using whatever type of connector you have at the end of the Bluetti 12 VDC high amp output cable.

Thanks Scott. Yes, I meant the 7 pin connector. I reverted back to my old computer days and 25 pin serial connectors. Brain freeze, I guess. Thanks again for the input.

IBM changed the EIA RS232 25-pin serial connector to a simpler 9-pin connector when they created the Personal Computer in 1981. I know this standard well because I had to study the RS232 standard in 1974 and read the original EIA documents, then use the info to modify a 300 baud acoustic coupler to work with telegraphic current loops (the RS232 standard uses +12 V to - 12 V signals). Now everyone uses the USB standard with only four pins.