BMW: Three beeps coming from car, beep beep beep, beep sound

Question
I have a 1986 325 coupe.  The car is in great condition, however, when I am driving, I hear a loud
beep, beep, beep sound (like a sound you hear when the radio goes into emergency broadcasting test mode, except it's broken into three beeps).  It sounds like it's coming from somewhere near the dash in the driver side.  It is very random, but I will hear it at least two or three times a day.

Any thoughts?

Answer
Andrew,
 This is nothing serious, just the on-board computer beeping.  If you look beside the radio, on the passnegers's side, you will see the on-board computer (OBC).  The OBC has settings, like time limit, speed limit, mileage limit, and when you set those, the computer will beep.  So someone was probably playing with the computer, and set the mileage or trip time to 20 minutes, and every twenty minutes it will go off.  So just hit the Set/Resume button, and it should clear out any settings.

 Good luck,
 Josh