Alright guru's here you go! I have a '75 that i've just started to use as a daily driver. its maiden voyage was 30 mi into LA and back. the next morning the battery was dead. i got her bump started and ran her for about 15min and got the battery charged again. let her sit for 15 or so and the battery seemed very strong. let sit overnight again and its dead. broke out the multimeter and there is definately a draw on the battery while the ignition is off (over 500mA). I've checked both lights (passenger and engine compartments) and they are off.

What other (unswitched) components could be draining my power or "sticking" on?

-Tommy

Since you have a multimeter, use process of elimination. Try pulling off a fuse at at a time to see if it makes a difference in the 1/2A load. If pulling a fuse doesn't make a difference, then chances are that it isn't the issue.

Even try disconnecting connectors, like the one to the relay panel or the one to the steering column. When disconnecting connectors, you may want to disconnect the battery first, then reconnect the battery after removing the connector. If you run out of things to remove, try disconnecting the starter (disconnect battery first).

Also try jiggling wire bundles as adjacent wires can short with 30+ year old insulation on the wires can become brittle and shatter in the wire bundles. Be gentle with the wires since rough movement can cause additional issues. Any removal or jiggling that causes the current to drop or rise gets you that much closer to the issue.

Spoke

Did the fuse thing with no response. i like the connectors idea... i'll try that next and then on to the wires. I'll post my findings. thanks!

Do you have a stereo and amp? Both can have constants on them.

Maybe one of your wires are broken and the electricty is leaking out on the

ground, next to the oil.

If you have multiple wires attached to the postive post of your battery (aftermarket or added on stuff), take each of them off, run your multimeter between each of those wires and the positive post (one at a time), and see if one of them is showing a draw. If so, that's the culprit!

I have found that 500 ma is about 1/2 the draw of a dome type light, maybe even 1/3 or so. I would make sure your not chasing ghosts. Make sure your seeing a true 500 ma. Maybe try to compare your readings with a draw you insert, maybe insert a test light and see what that shows and compare readings. You may be only seeing 50 ma and have a battery issue. Driving the car normally wont recharge the battery much unless you go on a long trip, anyway push starting a dead battery isn't the best thing for your alternator, your alternator will be hammering out at 100% for a long time trying to charge the battery. That really gets the internals hot. Charge the battery via a stand alone charger and test it or have it check at the parts store. When I charge my battery's (suspect ones) I always connect a volt meter, if within the first 3 minutes (normal charge rate setting) the voltage goes over 15.5 volts you battery is damaged internally. I often leave the volt meter on for say 15 minutes if it goes to 16 volts I would replace the battery. Simple theory is the faster the battery builds voltage the quicker it loses voltage. My 2 cents

so THATS it! i was wondering what those electrons were doing all over the place!

in all seriousness... thanks for all the advice. there's some great info here. im going to get on it tomorrow and solve this thing!

to answer some questions: yes i have a stereo, yes it has a constant but it isnt much at all. and i installed the stereo about a month before driving it to LA so if that had been the problem, i would've seen a dead battery before i even left. no amp

and i do have multiple positives, i'll try em all (boy it would really suck if they were allll drawing just a little...)

If you didn't notice my thread ("turn signal kills battery"), you might want to check that your turn signals are off. When you park with the left turn signal activated, it leaves the left turn signals lit, not flashing. There's no indication of this on the dash, and during the day, the lights are easy to miss.

HHHMm, how you say Merrrrcedes battery disconect unt vear a vatch?

Me a werry werry alayzzzyyy!