12V battery vampire leak
 

I've got a recurring problem with my 2006 HCH II's 12V battery. If I park it for more than 3-4 days the battery is drained to the point that the car will not start.

I replaced the battery last month and when I was out of town for a week, I returned to find that the new battery had suffered the same fate. I do not have any accessories or aftermarket devices installed and nothing is plugged into any of the cigarette lighter/power outlets. A bad ground?

I'm currently using a battery charger/maintainer when I'm out of town, and that works fine, but I'd really like to find and fix the problem.

Does anyone have a systematic method to isolate the source of the battery drain?

Thanks!

Re: 12V battery vampire leak
 

check unloaded and loaded battery voltages. Pull fuses to see how it impacts voltage. That should help you get to which system is the culprit.

Check out this video:


Steve

Re: 12V battery vampire leak
 

You could put a ammeter in series with battery (or if you have a fancy clamp on meter which would save you from disconnecting battery). This will show you the current draw. You can then pull fuses one at a time to see which one is the culprit!

A long time ago I had a car where the horn didn't work, but I had a 'low amp draw' draining the battery. It was the horn switch/relay that was stuck on, draining the battery.