ID this plug please

[HillbillyDeluxe39]

Its hanging on the passenger side next to the sway bar end link. I traced it back up to the harness that goes to the air conditioning resistors. One person told me it was for lighted steps, several others told me it was for ABS. I dont have front abs hubs but I am replacing the hubs next week and dont know which to order. I bought the truck used and dont know the history. If it is abs will it work if I hook it up or is there more needed in the abs controller department?