E-Gremlins Killing Battery

[Juice]

Last year I discovered that my battery was getting killed off pretty fast, but I was unable to do anything before the season came to an end. This year, as I was pulling the car out of storage, I found that my battery was dead, and threw an error code on the recharger. I decided to drop some big bucks on an Optima D35 Yellow top as a replacement, with dedication to resolve my battery drain issue to follow.

Upon reinstallation, I found that my external line to my amplifiers is drawing so much current that I am causing some arcing to take place. I think I have been able to isolate the problem to one amplifier, but the real problem still eludes me: why would an amplifier be drawing current when not powered up? From looking at it, we are talking some serious draw here.

 

[nsxtasy]

why would an amplifier be drawing current when not powered up? From looking at it, we are talking some serious draw here.

Interesting. I am only guessing - I am not an expert on these things - but I would think the reasons fall into two categories: (a) it's designed so that that's normal (such as the way a stereo still has the dial lit up even when it's off), or (b) it's not normal (maybe there's a short circuit somewhere in it?). Any way you can check with the manufacturer to see what a normal draw is when it's turned off?

 

[Briank]

The stock system has a one relay that switches the power to the amps. Most aftermarket systems use one multi-channel amp. Need a little more info here. Sounds like you have a aftermarket system with multible amps? If you have one that is bad and it's not getting an enable signal I guess you replace it.

 

[Juice]

Off the positive terminal, I have a single cable that runs to a fuse box that splits the line through 2 fuses into seperate lines. Each line then heads to the power side of an amplifier.

What I find curious is that when I take the main line to the battery, I will get an arcing effect (ZAPP!) when I touch the terminal. If I touch it multiple times in a row, it will arc the first time but not subsequent times. If I hold the cable away for a minute and then touch again, the arcing reoccurs. It is acting like a draw is forming on the other side. Mind you, the keys aren't even in the ignition while all of this is occuring. Why would an electical componant be looking for power without any "on" signal?

 

[Briank]

Sounds like you are getting a spark from a capacitor charging. Amps have capacitors.

 

[Juice]

That's what I have been thinking, but in all my years of working with amps, I've never seen draw this strong, or with the repeating effect. It is acting like the capacitor is charging, but then discharging spontaneously. If that is the case, I should be able to observe this phenomina on a trickle charger as well.

 

[clarknm]

This may be too simple, but I've noticed that my USASpec iPod adapter is always powered on. I would expect this to be switched power, but it doesn't appear to be. So, maybe check the wire you're using to switch the amp on? Make sure it's really off.

 

[TitaniumVtec]

Do you have any after market relays on your car for stereo, fogs, nitrus? I have a relay wired incorrectly one time and it was energized all the time. Cost me a new battey and hours of head scratching before I started to disconnect things. Unplugging the relay made a 'click' sound. That was my problem.

I would unplug an amp at a time and see how long the battery lasts. Sounds like the draw is pretty fast, so you should be able to figure it out quickly one amp at a time.

Good luck

 

[Malibu Rapper]

Have you checked the remote turn on line to the amplifier for voltage when the car is off? Are you sure your amps are off? I have seen amps draw current even when they are off, I always theorized that it was the internals going bad so the caps were somehow pulling current in through the power line and discharging.

 

[DrDave]

It's normal to see a small spark when you hook up the battery cable. You are charging a cap and energizing some systems temporarily. After a few seconds the system draw should go down to the normal ~35ma parasitic draw. You could easily measure the draw with a multimeter. The trick is to have the battery cable off the battery and touching the side of the post with your meter leads hooked up. This way you won't subject you meter to the large temporary draw. You will be doing this with your meter in the ma position. Some meters don't have the resolution in the 10a scale to read small ma loads.

You should be able to leave the meter hooked up while you disconnect your amps. It should be simple to find the offending component.

Dave

 

[Cozmo]

If it was really your amps not powering down your battery would probably be dead the next morning every time.

How fast of a discharge are you talking about? I'd expect the battery in any of my 3 cars to be nearly dead if it sat for a month or longer.

 

[Juice]

Cozmo, it was killing the battery within 2 days there at the end.

I need to find some time to get out there with the multimeter. I should be able to report my findings after this weekend.

 

[Juice]

WOW! Definitely the amp powering my subwoofer. I'm starting to suspect a couple of issues. I also noticed that my Accusump control valve doesn't work when this power line is disconnected. Since I didn't install either component, I'm starting to wonder how my Accusump was installed.

Must dig further.