Pump unit, valves, wiring harness?

Hello everyone, I'm new around here, but I've owned my 99' Prefacelift E46 for a couple of years and the ASC/ABS light came on. So I went to get my codes check (I'm not gonna throw money at it) and it came up with one code: 113, Pump unit, valves, wiring harness. I searched around the forums and no search results popped up. I assume/hope it's just some connector loose? I guess what I'm asking is, where's a good place for me to start to diagnose? If there is a thread with this code/problem please feel free to let me know please. Thanks!