Amp is killing battery

[DarkDragoon]

Me and my brother put in an older Kenwood KAC-7202 amp he had laying around into my car a few weeks ago, but the amp seems to kill my battery when left overnight. The amp is powered off when this occurs, the light goes off when the radio goes off and turns on when the radio turns on since the remote wire is hooked to the remote on the radio. I know it's the amp because if I pull the fuse from the power wire to the amp and leave it the battery doesn't die, however if I leave that fuse in the battery will be dead within a day or two.

My thought for why this is happening is a bad capacitor or something in the the amp that's leaking current or something along those lines. I have an analog voltmeter laying around and tested what i could by checking the voltage at the amps positive and negative terminals while the fuse was in and after it was pulled, and while it was in the amp gets the full battery voltage as you'd expect but once you pull the fuse the voltage slowly drains until it's empty. Now i'm not sure if it's supposed to do this or not but to me that seems like it means the amp is either consuming or leaking power, but i could be wrong about that I guess.

My question is does anyone have any insight as to what might be occurring with the amp thats killing my battery even though the amp is off. Also is there anyway I could wire a switch to the power wire going to the amp so I could switch it on and off instead of having to pop my hood and pull the fuse all the time.

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[Autotech91]

Check what the remote wire is hooked up to, if its not that test for stand by current draw

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[dev199505]

Unhook the remote wire from the amp and see if it still kills the battery also put a volt meter to the remote wire with the car off and see if it's still putting out voltage

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[DarkDragoon]

The problem isn't with the remote wire, its hooked up properly and even with it not hooked up the amp still kills the battery that was one of the first things I tested, which is why i'm fairly sure the amp has a bad cap or something thats causing it to leak current, would hooking up a switch like the one linked below work alright to cut the power to the amp instead of pulling the fuse all the time, until i get a new amp?

Battery Isolator Cut Off Power Kill Switch 400A 24V Key Waterproof Cover

 

[Papermaker85 5,000+ posts]

sounds like a short somewhere in the power supply.

 

[DarkDragoon]

Yea it could be a short or something as well, the amp is kind of old and has been banged around a bit, it works fine and everything just it kills the battery when the fuse is left in the power cord, which is why i'm trying to figure out if using a power cut-off switch would work for it so i don't have to pull the fuse all the time.

 

[avs20 10+ year member]

Why would you trust running something that has an obvious issue? Throw it away.

 

[DarkDragoon]

I plan on just buying a new one soon but i dont really use it that often mostly just to and from work so i figured i should see first if their was a way to remedy the problen with a $10 switch instead of buying a whole new $100 or more amp

 

[DarkDragoon]

Well after some testing it turns out it might not actually be the amp killing the battery and it may have just been coincidence that my battery hasn't died since pulling the amp's power fuse. I decided to pick up a digital volt meter and do some parasitic drain testing and found that something was pulling around .3 to .4 Amps or 300 to 400 milli-amps which is way more than the less than 20-25 milli-amps a car should pull and putting the fuse for the amp back in seems to make no real noticeable difference on how many amps are being pulled.. Turns out after pulling a bunch of fuses it seems to be the dome lights that are killing my battery. Even though no lights in the car are on for some reason something in that circuit is still draining power. I knew my wiring in the car was wonky since even with the key out I can turn on the wipers and any lights like the headlights or signals or the little light under the mirror, but I didn't realize it was this bad that somethings either shorted or wired wrong and draining power. I'm gonna keep testing more, by letting the car sit for a few days without running and see how much voltage the car is losing with the amp unplug and plugged in to see if it makes a difference, but after seeing how much is being drained by the dome lights circuit I think it's safe to say it's not actually the amp.