ABS fail light came on and.

Hi,

ABS fail light came on and ABS has not functioned since. Used to have issues when I first started the car that I would have to pump the brakes a little before ABS kicked in. Took it to a mechanic and he didn't have the right scanner to identify the problem. He did notice the fuse was blown for the ABS. He replaced that and it blew straight away. He didn't know what would cause that. Also the horn's fuse was taken out by the previous owner so the horn wasn't working. Mechanic put the fuse back in and was working for awhile but then it just started going off randomly without any touch.

Any advice would be greatly appreciated!

Thanks in advance,
Travis