why do most flatbed trailers have two electrical connectors?

Discussion in 'Flatbed Trucking Forum' started by scoobertdoo, Nov 17, 2022.

  1. scoobertdoo

    scoobertdoo Road Train Member

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    311756271_6146193058766265_6053366258785383495_n.jpg 312328964_5765430580182289_3453786904828243634_n.jpg 305672946_6095792780478501_1447859540257305688_n.jpg

    What is the second connector for? Do all flatbeds have a dump air function on the axles?
     
  2. skallagrime

    skallagrime Road Train Member

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    Not all, and it can be a function of age too. 2nd plug could be for abs if its older, center wire (blue) as abs is relatively new, that used to be what you wired the dump valve on. NOW the 2nd plug is for dumps, extra lights, oversize lights etc
     
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  3. scoobertdoo

    scoobertdoo Road Train Member

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    this one is a 2006, wouldn't that be abs on blue? So I can assume the second is for lights, or lift? and not necessary unless I need osl lights?
     

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  4. D.Tibbitt

    D.Tibbitt Road Train Member

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    Look under the trailer and see where the wires run. That will tell you what it's for
     
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  5. scoobertdoo

    scoobertdoo Road Train Member

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    I am looking at online ads. Not sure I want to start a negotiation by asking questions that an informed person would know. I like to pretend I know what I am talking about when hashing out prices :p
     
  6. D.Tibbitt

    D.Tibbitt Road Train Member

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    Oh ok I thought u were taking those pics in person.. The last flatbed I had, it was for extra lights you can hookup to a oversize load.. Some may be wired for a dump valve to the axles.. Some may have plug from factory but not wired to anything... No harm in asking the seller what the plug is for. It's impossible to know how everybody uses their equpment
     
  7. scoobertdoo

    scoobertdoo Road Train Member

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    How hard is it to add a dump valve on the rear axle? I have a super tight turn coming into my street for my house, and I am not sure I can make it without removing the stop sign
     
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  8. bad-luck

    bad-luck Road Train Member

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  9. skallagrime

    skallagrime Road Train Member

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    This

    No sane person selling a trailer should expect a buyer to know how the trailer for sale is set up, if anything, it shows knowledge that it may be different and that you may have to modify truck or trailer wiring
     
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  10. ZVar

    ZVar Road Train Member

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    Heck, it could also be nothing. Could be there for future use and not actually wired to anything just yet.