Jl Audio Amp (Alternator) HELP

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Apr 30, 2008 | 04:16 PM
  #1  
2005 C230k SS.

heres my problem. i have after market stereo system which includes a 500/1 and a 300/4 JL audio amp which i have in the car for about 3 years with no problem until yesterday. had the music on very load
(never had a problem before), then out of no where the highs and mids go out. so i pulled over to a parking lot to try and figure whats going on. so i turned down the volume, a second later the music was back on. heres the weird part the sub amp never turn off just the high and mid amp. now everytime i turn up the volume the 300/4 amp turns off but not the sub amp? i have called jL audio and told them what happen thinking its the amp but the tech told me thats its not the AMP at all. Amp is working fine. jl tech told me its because i have a second battery in the trunk and its over loading the Alternator. but i dont have a message on my screen that says anything about my Alternator going bad. does anyone know if my Alternator going bad on me. i have checked everything from the wiring to the battery and everything checks out OK. the only thing i have not checked is the Alternator.
the Tech fro JL told me to up grade my Alternator and this will solve my problem. so my question is has anyone up graded there Alternator for there stereo system and if so where to i go abouts getting one and how much should i be expecting to pay. THANKS
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Apr 30, 2008 | 05:36 PM
  #2  
while It very well could be the alternator, I would first start looking to make sure you didnt short the amp, and are not overdriving the load (ohms)

Many times, if you bridge one of the connections and run a impedance that the amp cannot handle, it will go down.

Another option is perhaps its going into thermal?

But, from being in the industry for many years, you have 2 batteries running off the stock alternator? If your going that route, get a new one or a new rewound core.

Quick test would be to disconnect the sub amp and crank it. If its wiring or impediance, you will have the same problem. If not, then disconnect second battery, and test the load again. Your lights and all will dim, but the amps should not go out.

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Apr 30, 2008 | 09:18 PM
  #3  
Had same problem.....
I had the same problem turn out that one of the wires in the amp was loose and the amp would go into protect mode when the wire made contact with metal. i fix the wire and problem fixed...
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May 1, 2008 | 12:42 AM
  #4  
The original battery and the alternator in your car is already a stud muffin. I doubt they are the problem. The Mercedes battery has more capacity than any battery you can buy after market. There are exceptions, but they are as plentiful as hockey players in New Mexico.

Your second battery is suspect. I assume you have a diode isolator to the second battery, but have you checked the specific gravity of the electrolyte in the second battery? Have you checked the liquid level? If it is down, add DISTILLED water ONLY. Measure the voltage when operating at loud volume on the amp terminals. It should be near the second battery terminal voltage, or you have a sniveling connection.

The Oregon mist so often endured in Portland is a cause of corrosion, and I would have you connections checked by someone who can measure the voltage drop across each one. I bet a simple clean-up is all you might need.
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May 1, 2008 | 10:41 PM
  #5  
Quote: The original battery and the alternator in your car is already a stud muffin. I doubt they are the problem. The Mercedes battery has more capacity than any battery you can buy after market. There are exceptions, but they are as plentiful as hockey players in New Mexico.

Your second battery is suspect. I assume you have a diode isolator to the second battery, but have you checked the specific gravity of the electrolyte in the second battery? Have you checked the liquid level? If it is down, add DISTILLED water ONLY. Measure the voltage when operating at loud volume on the amp terminals. It should be near the second battery terminal voltage, or you have a sniveling connection.

The Oregon mist so often endured in Portland is a cause of corrosion, and I would have you connections checked by someone who can measure the voltage drop across each one. I bet a simple clean-up is all you might need.
Moviela I enjoy reading your responses as I always seem to learn something new.
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May 2, 2008 | 02:27 PM
  #6  
ok finally after a couple of hours of checking the system over and over again. the problem was the the fuse between the two battery was blown ( i swear i checked it at least ten time). when i looked at the fuse without taking it out it looked ok. but when i finally took it out of the housing it was blown DAMN CALL ME STUPID. so to everyone out there that has a stereo system PLEASE TAKE A GOOD LOOK AT THE FUSE FIRST. it will save you a lot of time and frustration. Thanks to the people that replied to my post
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May 27, 2008 | 09:13 PM
  #7  
came across your post ... i just installed new components, subs and 3 amps... one 1000 for sub and 2 350 x2 for doors... funny thing is my volume fluctuates a bit between accelerating and sometimes when i am stopped.. any ideas what this could be from?
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May 27, 2008 | 09:21 PM
  #8  
my bad i think i figured it out... was listening to it in Logic 7 .... think it gets lower the slower i go ....louder the faster.. duh
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