Hello. My wife and I bought an '03 Mini Cooper (non-S) a couple weeks ago. With the key on, but engine off I can hear a ticking noise from the ABS unit. It sounds kind of like a clock. I don't remember if it does it while running and she took the car to the airport, so I won't be able to tell for a couple days. A couple questions:

1) any ideas on what this could be? i tried searching but didn't find anything.
2) am I going to cause any issues (like triggering a stored error code) if I disconnect the electrical connector at the unit to troubleshoot?

Thanks in advance.