Voltage loss after system installed
Thread Starter
Registered User
Joined: May 2011
Posts: 35
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From: Tennesse
Voltage loss after system installed I have a 500 watt amp, and only 1 10" sub hooked up..when Im idling with my stereo and A/C running the voltage went low into the orange to about 9 or 10..I just replaced the alternator and belt tensioner and the battery is good. I hooked up a capacitor and now when I have the a/c off(idling) I'm at 13 volts, when I turn the a/c on and idle I'm back at 9 or 10 volts..my battery is reading 12 volts as well as the capacitor..is this normal or is there something going on? I just dont wanna kill my alternator. thanks
Registered User
Joined: Jun 2011
Posts: 12
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From: Hot Springs Arkansas
4 gauge should be plenty for only 500 watts. Depending on the internal wiring of your amp you may also consider a 1 farad cap to compensate. I used to run 1900 watts and 1500 (Peak) was on the subs alone. The stock alternator, 1 farad cap (stinger), 4 gauge power, and stock alternator was fine. Also make sure your ground wire is less than (15" 20" max) and making good connection. If you start pulling over 2000 watts then definitely go with 2 or 0 gauge wire.
Also, depending on the build date of your car, create a separate and isolated ground wire for your after market head unit. I have experienced floating grounds before using the stock wire and it did funny things with the amps including cutting out and volt hogging. That one simple change fixed the problem on a few setups but not all of them. I really never understood why some cars had this issue and some didn't. It doesn't sound like you have it, but it is always a good thing to isolate that ground wire.
Also, depending on the build date of your car, create a separate and isolated ground wire for your after market head unit. I have experienced floating grounds before using the stock wire and it did funny things with the amps including cutting out and volt hogging. That one simple change fixed the problem on a few setups but not all of them. I really never understood why some cars had this issue and some didn't. It doesn't sound like you have it, but it is always a good thing to isolate that ground wire.
On The Tree
Joined: Jul 2011
Posts: 190
Likes: 1
From: Woodinville, WA
i think its a ground problem too. your ground should be very short to help with voltage. wire it to the metal in the back of the trunk. also you should use 4 ga to the amp from the battery. if that doesn't work then go big 3
