my 1995 k-3500 abs light is on. why. i went o reilys and the have a ob1 scanner. and it reads abs codes. it says my truck is not responding. it did say my truck was a 1995 so i think it reads my truck. just not the abs codes for some reason. i have an old obd 1 scanner and it has an abs swiutch. it says 73, then 86 then 12 then 25 then 35 then back to 73 and so on. i tried unhooking the battery for an hour. it will not clear. it does seem the rear braks do lock up. not the front. but that might be because it light in the back. thank you much.