Kevin O'Brien wrote:
snip
As I still rent from my local FBO, and they have apparently had a few
acft
returned in the past with dead batteries, they have summarily
disabled all
of the cig lighter sockets in all of their acft. I fly with a
PDA-based GPS
which requires a 12V source for power, but only drains 250mA during
operation, so I keep a small gel-cell battery in my flight bag with a
cig
lighter socket pigtailed to the terminals.

Sort of a non-sequitur to your question, but I always ask this:
Do you have a fuse right on the battery?
A really easy way to do this is a short jumper with female connectors
on both ends. (I've actually soldered two back-to-back and put
heat-shrink over them) Slide one end on the battery terminal, the
other end to one tab of an automotive fuse. Your former power
connection then slides on to the other tab of the fuse. Cheap. Easy.
Safe.

I had a setup similar to yours for a handheld radio which I would have
_sworn_ would not short. It did, though. Caused some smoke, burned
through my little custom-sewn denim bag, and gave an enormous shot of
adrenaline.

Tim "once burned, twice shy" Ward