"Sam Nickaby" > wrote in message
.. .

Sometimes intermittent battery drain with the engine off can drive you nuts.

Simple reasons are lights (glove compartment, trunk, etc) that may not
always
turn off when they should, relays that lock on when they shouldnt.

Since it doesnt always happen, it can be hard to find.

You can
-buy a battery disconnect, and decouple the battery every night. It works
but is a PITA
-remove a different fuse every night, until you find the circuit that is
offending. (Some circuits are
perhaps on fusible links, not fuses) Then start down the circuit,
eliminate branches as you go.

This happened to me on an 89 Buick Regal. I finally found it (whereas a
dealership or independent
mechanic might have given up, or at least charged me a ton) by the method
mentioned above. The item
causing the problem was a relay which activated the seat belt
retractors...in the cold of the night, and
even then only occasionally. It was enough to give me a flat battery every
morning until the case was
solved.