caps draw from battery when car is off?

Hi guys,

I have a bit of a problem.

My system consists of (3) 15" JL subs, (3) 1,000 Kenwood amps, (1) JL Audio 500 watt amp, line driver, cross over, and (2) 1 Farad caps.

My car for some reason is always dead if sitting for a week without use. I disconnected my Viper alarm completely to see if the drain was from that - and I had the same problem - so my alarm as a culprit is out.

I bought an Optima Battery Yellow Top, same problem. Got a Red Top - still the same problem. Any battery put in my car drains.

Installed a high output alternator - and while my lights don't dim, and everything runs great when everything is powered on - the battery is still completely dead if sitting for a few days.

My local audio shop swears up and down it's because of my 2 caps. They said being I did the big 3 upgrade and purchased a high output alternator, that the caps simply are not needed. After he told me that, I did a google search, and from what I can read, caps don't drain the battery when the car is off. The manager at the shop says it's the caps and they aren't needed, a google search stated the complete opposite.

So, now I'm coming on here to hopefully get the right response. Should I ditch the caps? And is that the culprit draining any battery that is dropped in my car?

Thanks in advance

My Viper does have a starter kill. But as I've said, I completely pulled the power from the alarm, and it still was an issue.

Whiterob, If my car is running, and I go to start it the same day, or even a day or two after - it's fine. It's when I don't drive it for a week, it just doesn't start. I guess I can take the fuse for the audio system out, but even doing that - being the caps store energy - would it even do anything?

Really, this issue only started after finishing my system - so it has to be related to the stereo - of course I just assumed it was the caps.

Well, the caps did help before I had my HO Alternator. Nothing was dimming, etc.

But honestly, if it's not going to help my issue - i'd just keep them in there.

Wire a current meter in series with the ground wire on your battery and wait 5 minutes and observe the current draw of the system.  Anything over 50mA typically points to something wrong.

The problems with capacitors is when they start to fail they will have excessive leakage current.  Because capacitors try to equalize their voltgae with the system voltage execessive leakage current will kill your battery.

However, the thing to realize here is that caps are in EVERY electronic thing in the car - not just your audio system.  Typically, though, aftermarket equipment is built using inferior components to OEM electronics, so its always a good idea to start eliminating aftermarket stuff first. 

Once the current meter is installed I would disconnect the caps.  If there is no change in current then disconnect the amps one at a time, observing the current after each disconnect.  If you get to the end of all your audio equipment and there is still excessive current draw then start pulling fuses.  I would start with fuses for the audio system and the dome light, and then start pulling fuses for other electronic components, again checking the current draw after each fuse is pulled.

Depending on the make/model of your car you may have components that "go to sleep".  If this is the case you will need to wait 5 mintues after shutting all the doors before the current will settle and give you an accurate reading.