your car should run without the battery if the alternator is OK. start it up and remove the battery cables.
you might have a direct positive short to ground - you are going to need some sort of volt meter. they're only $6 $10. you would lift the ground wire and put the voltmeter between a solid ground and the negative post on the battery. if you have a short, you will get a reading.
I've had a brake light socket short to ground and the ignition wire short to the starter.
does the battery drain down overnight?
Butch
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