New Sound system = lights dimming, bigger alternator?
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New Sound system = lights dimming, bigger alternator?
Just put in a new sound system. Just a sony head unit and an alpine type x component speakers. The system turns on and off speriodically and all the lights dimn. I know when I put my 3 12" jl subs back their the system probally wont even run. So do i need a bigger alternator? If so where do I pick one up, local autozone? If not an alternator than what?
I have a 600w sub amp in my car. When it was in my mustang it would dim the lights, the RX never flinches. How is your battery? Maybe try grounds as already suggested.
Check your battery connections and clean them up if they are dirty. My connections were dirty and the stereo (aftermarket) would periodically shutoff. Cleaned them up with a little baking soda and water and the stereo has no problem now.
You Need A Capacitor It Will Keep Your Batt With Juice Everytime You Hit A Bass Note The Stored Energy In The Cap Will Give It The Boost That It Needs And Will Keep Your Car From Dimmin
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Check the voltage on your battery before you replace the alternator. My PC680 has a bad cell and every time I touch the brake the stereo shuts off. It's so annoying, it's better just to leave it turned off.
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Originally Posted by mazda/feed
You Need A Capacitor It Will Keep Your Batt With Juice Everytime You Hit A Bass Note The Stored Energy In The Cap Will Give It The Boost That It Needs And Will Keep Your Car From Dimmin
No. The batt/alt will supply the cap with energy. Is has a much higher discharge rate than the battery has and can deliver the power to the amp when necessary. It's temporary storage, nothing like a battery.
With just a head and speakers, you do not need a cap, and if you did, anything you'd buy at a normal store would be such overkill. Most caps people buy are overkill for what kind of sound system they have. I've got a 1/16 (if I remember correctly) cap from a PC supply store. That's sufficient. Don't need some .5 farad cap, let alone a 1 farad version.
Keep in mind that the stock wiring to the head sucks at best. You should run a larger ground and lead to it. I think it's 14 or 12 gauge now. 8 is a good start.
If that head is dimmimg your lights, you have other electrical issues. I can't see a head pulling that much.
He doesn't need a capacitor for an aftermarket head unit. He didn't say the lights were dimming when the bass hit, he said the unit was having other problems. I bet the radiator fans draw more amperage than 90% of all head units on the market. And they don't have capacitors.
Originally Posted by Railgun69
That to me? Yeah...I didn't say he needed one, though I did misread his post. I see your from IL too...PM me about RC3.
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I installed it and everything works fine. Sometimes its fine and sometimes its bad, I will be driving and the lights will dim than the hu turns off than on and than the lights turn back on. Ground is good, just checked it. Capacatior is not needed at all as I do not even have any amps. It should be doing this as it shouldnt be drawing that much battery. I took it for a 10 min drive it did not do it once. But before that on a 10 min driver it did it like 10 times. Will I need a new alternator when i get new subs, will be two 500/1 amps and a 100/2 amp with 3 12" jl subs rated at 300 rms each. I know I am going to need a new battery so thats next. Any other suggestions.
Make sure you are getting good ground.. you are nowhere near in need a capaciter.. does everything dim when a bass note plays or just randomly?
Mikey M.
Mikey M.
Last edited by Spirit_Rotary_7; Dec 18, 2004 at 12:07 AM.
I agree - time for a general charging system tune-up. Clean the battery terminals, make sure you've got a good battery, and clean the main battery ground points. Also, if your car is over 100-120,000 miles or so and on the original alternator, the alternator itself might be getting weak. The FD's stock alternator is VERY strong and puts out a LOT of amperage.
I've got an Alpine head unit running separates up front and coax's in the rear (no amp just yet) and have NO dimming or other problems. The stock alternator, with everything running well, should run QUITE a bit of stereo equipment.
Dale
I've got an Alpine head unit running separates up front and coax's in the rear (no amp just yet) and have NO dimming or other problems. The stock alternator, with everything running well, should run QUITE a bit of stereo equipment.
Dale
Try disconnecting your stereo so you can be sure that's your problem. You definately have something wrong. It could be wired incorrectly or something shorting out somewhere, either way, not a safe thing.
i must say, the most intelligent engine guys and most dont know anything at all about stereos.
he said the system turns off. im guessing that means his head unit is shutting off. what does this mean.... 1)improper grounding 2)improper power 3)not enough power to the headunit
I'm guessing that since it is a SONY headunit it does not require an external power source. That means it IS the ALTERNATOR or grounding or the power. heres how to determind what it is: tell me:
are the components run off amp power? is the head unit? once you give me that I will tell you what is wrong. damnit..i cant rebuild our engine...but I can hook up a mighty fine system.
he said the system turns off. im guessing that means his head unit is shutting off. what does this mean.... 1)improper grounding 2)improper power 3)not enough power to the headunit
I'm guessing that since it is a SONY headunit it does not require an external power source. That means it IS the ALTERNATOR or grounding or the power. heres how to determind what it is: tell me:
are the components run off amp power? is the head unit? once you give me that I will tell you what is wrong. damnit..i cant rebuild our engine...but I can hook up a mighty fine system.
Originally Posted by WinterUSMC
i must say, the most intelligent engine guys and most dont know anything at all about stereos.
he said the system turns off. im guessing that means his head unit is shutting off. what does this mean.... 1)improper grounding 2)improper power 3)not enough power to the headunit
I'm guessing that since it is a SONY headunit it does not require an external power source. That means it IS the ALTERNATOR or grounding or the power. heres how to determind what it is: tell me:
are the components run off amp power? is the head unit? once you give me that I will tell you what is wrong. damnit..i cant rebuild our engine...but I can hook up a mighty fine system.
he said the system turns off. im guessing that means his head unit is shutting off. what does this mean.... 1)improper grounding 2)improper power 3)not enough power to the headunit
I'm guessing that since it is a SONY headunit it does not require an external power source. That means it IS the ALTERNATOR or grounding or the power. heres how to determind what it is: tell me:
are the components run off amp power? is the head unit? once you give me that I will tell you what is wrong. damnit..i cant rebuild our engine...but I can hook up a mighty fine system.
if its just the headunit randomly quitting, its probably the wiring to the headunit. I bet all his connections are just twisted and black taped together.
theres not much to know about a stereo.
I run a 1500X1 rms amp off my stock alternator it works fine, I have a 1fard cap. even before i had the cap i notice hardly any problems with diming. I would suggest checking all your grounds, try getting power to the headunit from a different source.
and dont use black tape, unless you want it all getto, headshrink it....I learned this the hardway..
and dont use black tape, unless you want it all getto, headshrink it....I learned this the hardway..
Last edited by MrRx; Dec 18, 2004 at 03:07 PM.
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