headlights dimming

**Custom04Chevy** · 08-24-2009, 02:29 PM

OK so a couple weeks ago I put two JL Audio W3V2s with a 500 watt JL Audio slash series amp in my truck. I noticed a couple days ago while I was driving that the headlights dim every time my subs hit. Is there any way that I can stop this from happening? I have been told that there is something out there that I can plug the amp power wire into that will keep it from draining so much power from the battery, but I can't seem to find anything about it anywhere.

**ippielb** · 08-24-2009, 02:46 PM

All you need is a capacitor.

**Jimmiee** · 08-24-2009, 03:18 PM

Originally Posted by Custom04Chevy

OK so a couple weeks ago I put two JL Audio W3V2s with a 500 watt JL Audio slash series amp in my truck. I noticed a couple days ago while I was driving that the headlights dim every time my subs hit. Is there any way that I can stop this from happening? I have been told that there is something out there that I can plug the amp power wire into that will keep it from draining so much power from the battery, but I can't seem to find anything about it anywhere.

What size battery are you running?

**2ToNe04** · 08-24-2009, 03:58 PM

Originally Posted by ippielb

All you need is a capacitor.

Capacitors dont really even do anything, from what ive read and seen on my truck. Theyre kinda good when you just have your key switch on and trucks off, and your hearing loud music. It helps your battery not die, and ive seen some of my friends cars, still die out.

I would consider a red top battery or something much better than your stock one.

im running 2 12, 2 amps, 2 TVs, i have a yellow top battery from autozone, and there is no problem with dimming not even when the bass hits really hard.

I plan later on in the future when i bag my truck and get some efans. Im going with a higher voltage Alternator, and an extra battery. Maybe you might want to look into that if you get a big system in there.

**vncj96** · 08-24-2009, 07:17 PM

You need a bigger alternator or your battery is dying, the amp you are running is not strong enough to pull power from the headlights even at idle.

**Jimmiee** · 08-24-2009, 08:03 PM

Basically the alternator's job is to charge the battery. That's all it does. Any voltage the system needs it takes from the battery. The battery stores the energy until it's needed. If the headlights dim when the amp pulls voltage from the battery the battery is either in a state of discharge or it's capacity is too small for the amp.

**bill190** · 08-24-2009, 08:11 PM

Are your add-on devices wired directly to the car battery or the large cable from the car battery using large gauge copper wire?

Wires a like a water pipe. If you have a small water pipe like the small water tubing on the back of a refrigerator and connect a water faucet to this, not much water will come out and there is no way it will supply both the refrigerator and the faucet at the same time.

But if you have a large fire hose size water pipe going there, it would easily supply the refrigerator and the water faucet!

Same thing with wires. Large wires can supply multiple large loads at the same time. Small wires can't.

At an automobile factory, they determine the amperage loads on each circuit, then use the correct size wire for those loads. Then use the correct fuses for the size of wire used.

Wire size table...
http://www.offroaders.com/tech/12-vo...gauge-amps.htm

**Kaiser-Wave** · 08-24-2009, 10:29 PM

in my opinion red tops suck if you want a good and even stronger battery get the kinetik HC1800 however getting the battery isnt going to fix the dimming you need more amperage, i would take out your alternator and run it to a shop and have it rewound to around 180 amps (our alternators can actually go to 220 thats what i did) and you will never have another problem again, although a battery would help after you do that because the kinteik's are specifically designed for heavy battery usage.

**2ToNe04** · 08-27-2009, 12:25 AM

Originally Posted by Kaiser-Wave

in my opinion red tops suck if you want a good and even stronger battery get the kinetik HC1800 however getting the battery isnt going to fix the dimming you need more amperage, i would take out your alternator and run it to a shop and have it rewound to around 180 amps (our alternators can actually go to 220 thats what i did) and you will never have another problem again, although a battery would help after you do that because the kinteik's are specifically designed for heavy battery usage.

Just go to the junkyard and pick an alternator from a HD truck

**MeanGreenMachine** · 08-27-2009, 10:25 AM

I had the same problem when I first installed my system. I upgraded the wiring to 4g for all the grounds and battery connections. The problem went away. I also upgraded to an HO alternator, but I had a problem with it and had to remove it. However, I still did not have the dimming lights, so I believe the wiring was the real fix.