Van Vs Flatbed Hookup Cable

Can anyone tell me why dry vans and reefers have one electrical hookup to the tractor and step decks/flatbeds have two, also if I'll want to start pulling flatbed and my tractor has only one electrical cable, will I be able to add that 2nd hookup, and how expensive would that be? If someone could shed some light on it, I'd really appreciate it, just doing some research on switching to flatbed..

That's an interesting question. I don't have an answer for you because I pull reefer and I haven't looked that close at a flat bed maybe one of our flatbedders knows

The second pigtail is to operate things electrically from the cab. Such as suspension dump valves, lift axles and oversized strobes just to name a few.

Zar Q, Pat is right, that extra pig tail provides power for extra functions on the trailer. Many, if not most, flat-bed trailers do not need an extra pig-tail though. I run flat bed and have literally pulled hundreds of different flat-bed trailers. None of our trailers need the extra pig-tail.

Are the pigtail sockets different or do you look at the lights to make sure your in the right one? I'm just asking because this is interesting and I think I would like flatbed if I only worked in Canada or Alaska lol. I can't do heat so trying to tarp and crap in the summertime is just no.

They are different. You can't get them hooked up wrong by accident.