97 Ford Explorer battery going dead

Question

On Friday, my girlfriend's '97 Ford Explorer v6 lost electrical while driving. We were able to get it going again with a jump start. Lost electricity (lights / gauges) while driving, but were able to drive it the rest of the way home. Battery was dead in the morning.

I tested the battery and the alternator - both were shot (stock alternator, 3 year old battery), so I replaced both. Yesterday, she called me from work and said her car started, shuttered, and died. However, it started up after waiting a few minutes.

This morning, she called and said it was completely dead. No lights/windows/power locks, and no cranking. Wouldn't even start with a jump, though I'm not sure if she jumped it correctly.

On to my question: Is there something else that could be draining a brand new battery? I found something on another Q&A site saying something about the connectors on the alternator, but I know I tightened down all the connections, and they had good contact.

Thanks in advance.

Answer 1

First thing to do is to check for short circuits. With the battery fully charged and nothing switched on, pop an ammeter on the battery and measure the power draw - there will be some to power the alarm & radio preset, but that should be pretty tiny. If there is a large draw, you've got a short and the tedious job of tracking it down begins...