ok... well if you set the multimeter to read amps, disconnect the negative wire from the car battery, hook one end of the multimeter up to the negative connector of the battery and the other end up to the wire that normally connects there. The number on the screen will show the number of amps that are being drawn. Let's get that number and see if something is up.
Oh and the multimeter might have two positive connectors on it. One will be fused and one unfused. Use the unfused one for this test since normally the fused one only allows 400 milliamps.
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