Hi. So I'm grabbing my hair for few hours trying to figure this out....

I had a bad cell in the battery that resulted in the strained alternator.... the car was draining recently but the voltage when running was low too so I thought it was the alt, but it was a bad cell in the batt.... anyhow, alot of money went though and its fixed now...

But the real problem is that I had a 500/1 running the subs, two stage of fuses cuz im running a front stage from 300/2 and the 500/1 just blew ... I turn the car on then off and put the key in acc..... (stereo was turned down to 0 volume)... then voltage dropped to below 10 cuz of the bad battery and i heard that type of pop sound when the amp cuts out or just turns on but slightly louder so i knew something went wrong... open the back, smoke from the 500/1.... subs still have 1.5 ohm like they used to so it couldn't be them.... fuses untouched.... when i took it apart it looks like one of the power transistors overheated.... but its just a speculation.... although smoke came out from the amp, there is no burned, scorched or popped components.... the bad smell is near the transistors so im sticking with that theory....

I would not even question this if it was Lanzar amp, but this is the "immortal" jl, that doesn't need fuses, has self protection and even low load protection.... how in the hell did it fried itself when voltage went down?


edit:

After some thinking/ reading I could come up that when voltage was spiking it strained the regulator .... then when it went low it just couldn't take it anymore and blew.... i guess its the 1.5ohm-4ohm constant power output that screwed me over on this :/....

 

Identify the transistor that went bad, phone around to electronics repair places near you and you may be surprised how easy & cheap it is to repair.
I just blew a transistor on my 20 year old Alpine 3539, and with 2 phone calls and a 10 minute drive, I had a $5.75 solution to my problem in hand. Fired it up tonight, voila!
Hope your repair goes as smoothly.

 

I'll give it a go, since I'm broke it sounds like the best solution lol... But I've tried fixing and amp with bad transistors before... And it was a chain reaction with alot of components being faulty... You gave me some hope on this one, so I'll give it a try

 

So i called the Tech from JL.... they said I surged the amp.... I get it if I was disconnection the battery or boosting the car... but the voltage drop could cause a surge? That doesn't make sense to me,,.,, he just kept saying the same thing over and over again.... and didn't really explained it... I tried looking it up and no luck on such a scenario... Can anyone shine some wisdom on me regarding this?

 

pretty sure the fuse would blow first if it got a surge ....

 

^ Not always. Of all the parts in the amp, the fuse it the most tolerant of over voltage or over current situations. In fact, a fuse will pretty much ignore voltage, it cares about current, so if your regulator packs it in and allows 20v+ down the line, the fuse will probably be the only thing that doesn't blow! Sorta hinky..

 

The same thing happened to us on 3 amps, before we realized that there were voltage spikes, I didn't concern myself with the first 2 -customers and they were used, standing voltage 13.4 would spike to almost 17 when running...ended up being a split wire and an "Arcing"effect was happening....BTW Paul is right, understanding "Voltage" and "Current", fuses commonly blow when the current is "inturrupted"-ground short etc.

 

Any updates? Would like to hear if you got the cause nailed down, or even fixed?!

 

An alternator with no load (because of no battery or a bad battery) can let its output voltage run away... this was likely the cause assuming nothing is wrong with the regulator...