Can a amp and subs single handedly ruin an alternator??

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Mufasa1987

New Member
I just heard back from my mechanic about why my new alternator mysteriously failed again. When I had it replaced back in September along with the starter his explanation as to why everything failed was because I have 2 12'' subs and a 1200 watt amp to a panasonic cd player, and that caused the alternator to fail. When I just heard from him today he claimed that the amp was plugged back into the radio (which unless someone broke into my car and plugged it in for me) it was not. Voided the warrantee but now he's doing me a "favor" and fixing it.
 
So the mechanic unplugged it because it was the "source of the problem" he claimed, now claims it was plugged back in and thats why it broke again (dont forget it wasnt plugged back in) Did I fall victim to a pathetic attempt to be scammed?
 
very well possible being scammed bro , but with a stock alt. and a 1200 watt amp it could mess the stock alt up. they make a aftermarket alt for those applications. when i had my system in my ranger and all the kc lights on it i had to get an after market alt. i think it was a "stinger" alt.
 
He's saying the amp wasn't plugged in for the second alternator..

Yes, it's a scam or he's just trying not to put the blame on himself or his work. Was the replacement alternator new(did he buy it or you buy it?).
 
yea after i posted that i was tryin to find the post again and add to what i wrote .. sorry just answered the first question
 
right, he claims that the amp was plugged in (after he unplugged it when he replaced the alternator the first time) the second time, so yeah I thought it sounded kind of fishy. I mean I know its not great for the alternator but ruining one? I dont think so. And I do believe both times that we bought a new alternator, well he got it through whomever he gets his parts through. If im not mistaken he said he was going to "fix" this one that just went
 
So now im not even sure if the problem that keeps causing the alternator to fail is fixed, well in fact I know its not. Are there certain tests that can be done to eliminate possible causes?
 
While I can't say if the mechanic hooked things back up to try to put the blame on the amp... a 1200w amp can destroy a factory alternator.

I did car audio for 8-10yrs as a living. depending upon the amp and the load that it pulls it can put heavy strain on the alternator.

If you are running your system hard and seeing your headlights or dashlights dimming when the bass hits, this is a sign that not enough power is being created to keep the amp running at 12v. Which means your factory alternator is under a hard strain to recharge the battery.

You can put a band-aid on the system such as a capactitor which is run in series between the power and the sub amp. However this won't resolve the problem as the capcitor can only store so much energy and in music which uses alot of bass notes it won't be able to charge up and you'll once again be putting a drain on your amp. Other option is using a second battery such as a gel-cell or a deep cycle marine.

As noted above look at a high-output aftermarket alternator if you are running your stereo system hard for a long term fix.

If you don't mind me asking, what is the fuse rating on the Amp itself and what is the amp and the model? If you have your spec-sheet for the amp look at it (or the manufacturers website) and see what the load pull is. Then look and see what the output of your alternator is. You'll want your alternator to be able to put out more than what your amp is pulling, ideally 25% more.

You can buy a branded after market alternator like Stinger, but look at big bucks... try seeing if you can have your alternator rebuilt, but to a higher spec by a company who does this, will be cheaper and it will bolt back into factory location without any mods, after market upgrades can often require adaptors.

good luck resolving the issue.
 
I have two 12" subs and two 10" subs in my trunk right now with the two 12" running 1400 watts each and the the 10" are running 1200 watts each and the only thing I have extra is a 1.2 farad cap. Been running it like this for two years and still have the stock alternator. I maybe lucky but how long did your alt. last?
 
I know i am a little late but here we go. It sounds like you have two problems 1.the ground between the motor and the frame is more likely failing causing resistance so upgrade your ground wire's to two 4gauge from motor to frame. 2. your battery it might be to small if that so that will kill your alternator over time DO NOT USE deep cycle marine battery they are designed to let power out over long period of time not good for a amp that wants power now i hope this helps you. By the way i been doing high end car audio for 22years now.
 
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