If you don't happen to have an inductive ammeter as Steve suggested you can use a digital volt meter which may be more readily available. Go to a store like Radio Shack and buy a 1 ohm 10 watt resistor. Remove the negative lead from the battery and connect the resister between the battery terminal and the negative lead. Read across the resister with the voltmeter. Any reading above .05 volts indicates excessive current draw. Continue as Steve suggests with fuses. I might also add that before you go through all this that you have the battery checked by someome who knows batteries. I don't mean someone who sticks a meter on it. I mean have someone do a cell for cell specific gravity test, a load test, etc.You could have a failed battery. I'm not going to call it a bad battery, because I don't feel that disciplinary action is appropriate for batteries. A little humor there.
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