need some ideas to fix it.? (1997 GMC Jimmy) Battery will randomly start loosing it's power and not have enough juice to crank it over, At times it will fire up just fine, sometimes it will have enough juice to turn it over for half a second and will begin just clicking, and sometimes its so dead it doesn't light anything up when i open the door or put the key in...Just bought a brand new battery ~2 months ago, alternator has been tested and is working fine...We think something is drawing power from the battery when it shouldn't be, but we can't find the problem. Any ideas? Thanks.