ABS light issues

I have read several posts concerning the ABS light but none to the same issues i am having...
I am running a 2014 Peterbilt 379 and retnouer low profile stepdeck trailer.
The trailer abs light comes on and goes off randomly. I thought it might be from rain or shorted wire cause sometimes it happens after hitting a good bump...
Anyway i pulled over, wiggled the pigtail around no change...light still on. So then i disconnected pigtail at tractor and still have abs trailer light on dash. I have shut the tractor off and on several times and the light is still on...not sure where to go from here or what to tell the technician when i get to amarillo....thanks for the help...

 

The trailer light does come on...3 out of 4 of my last trailers had same issue, some of the other guys had same issues..we checked sensor positions on a few of the trailers but not sure if that worked. First time pulling this trailer.. plugged pigtail back in, when i left rest area light went off for a few seconds and then came on and flashed twice. Cant get it to do it again. Thanks

 

Got to shop, Utility Trailers in Amarillo just down the road from Petro...2 cables were pinched on front axle...also found broke shocks which probably allowed the cables to get pinched...$536.00 which i thought was pretty fair...

 

Wires were $40 each and shocks were $50 each...then the shop fee and zip strips they used and other misc. about 3 1/2 hours labor...will def go back there...boss man was happy with the price...will have the local shop replace the other two shocks when i get back...