Cleo Frank wrote:
Background: 1990 Mazda Protege, very well maintained, very clean
under hood. Last night it started as usual. I drove it to the dumpster
at the edge of my property to dump some trash, stopped the car,
and cut engine. When I tried to start it back up, I got the usual
click of a dead battery; digital clock very dim etc.

Sounds good. It would be a good idea to check the voltage with a meter
when running and not running so you know if it's just the battery or something
else, but that would indicate the battery.

Went to NAPA today and bought topnotch battery (the same
kind that came in car when new). I did accidentally install
it backwards (neg lead to pos post and pos lead to neg post),
got some sparks, but the battery is now securely connected.
The lead clamps are pretty clean and don't appear damaged.
But no power whatever, clock dead, nothing.

Ideas?

If you are lucky, you have just blown the fusible links on the battery
lines. More likely you have blown some fuses too. Worst case you've
blown the alternator, ECU, and a bunch of sensors with the reverse polarity
as well.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."