[s-cars] Buzzin'

[tblack]

Standing in the garage the other day working on something unrelated to the car and I hear a rapid interupted buzz which lasted a few seconds and stopped. A few minutes later the same thing. I opened the driver's door and the noise seemed to come from the left side of the dash but it stopped before I could determine the location. The battery on start-up yesterday was definitely lacking its usual zipp but started without any hesitation. This morning, same thing, so the battery is being drained. Later, I happened to be in the garage when the buzzing started again and determined that it was coming from the area of the driver's foot rest; took off the panel and the buzzing started again and was coming from a small 1" cubic shaped "relay?" 859 951 254 With 218 stamped on top, also has 12V-20V 50A on it. This buzzing seemed to awaken the large relay marked 441 959 257B which started a rapid clicking, it has 329 on top.
I have no idea what is causing this peculiar behaviour and would appreciate the list's wisdom in sorting it out. I have not been aware of the buzzes and clicking while driving but that could be because it is muffled by engine/tires and wind noise.
Any help appreciated.
Tom Black.