Danman114

Got a problem - Installed my amp and sub, and it worked fine for about three minutes, and then when i turned my car on the next time it blew the fuse, and when i replaced the fuse its not working ( it didnt blow another fuse). the amp is a rockford fosgate and the sub is infinity. its properally hooked up to the battery and grounded... any one have any ideas as to the problem, my friend knows more about it than i do, but he was sure that replacing the fuse would fix it... help would be appreciated

doubledeuce2k2

iTrader: (20)

what fuse did it blow? the one on the amp or on the battery cable?

have you tested the speaker to see if it still works? maybe battery test or on another amp that you know works, if possible.

what models of sub and amp are they? telling us the brand and asking for help is like asking how many horsepower a ford has...

does the amp itself turn on? is it in protect mode when it does?

WhiteRabbit

check the impedance, I would bet that the subwoofer, if properly hooked up, is too low fo a load for the amplifier to handle. would draw too much power and overheat or blow.

the usual result is blown output transistors.

this is a classic case of that, I would look into that first.

best way to test the amp is to remove the load, remove the signal, remove the remote wire, adn bridge remote to power with a paperclip or wire or something. its the fastest way to check if the amplifier works, often amplifiers will not turn on with signal or load issues, this lets you isolate those potential issues.

if the amplifier still doesnt work, then check the power to ensure you are getting 12 volts from it.

if you are, then the output transistors on the amp are probbaly fried. its a classic set of events.

Danman114

i get more info for you by tonight, and hopefully test it out like white rabbit said. One more question, could bridging it like white rabbit said blow a fuse? because i am almost positive that my friend tried that yesterday... I ll double check with him, he knows more about it than ido... thanks alot though

WhiteRabbit

alright, a buddy of mine did the exact same thing you did (except I know he blew his amp through low impedance, you its jsut theory so far) and here is his story:

He bought a couple extra tweeters, cheap junk, but massive power handlers, blah, blah, blah. anyways, they are 4 ohm drivers each, we decided to wire them in series for a 2 ohm load and run a single wire to the amp. I hook it to channel three, and tell him that its because the load is too low for the audiobahn amp to handle mono.

well, the next couple days later, he tells me he bridged the amp, is that ok? I admit my surprise teh amp still works, and tell him, that if it works now, then yeah, its fine, that some amp,ifiers are stable that low, edspite not being told so in the manual, thank goodness he didnt blow the amp!

two days later he tells me the rear channels of his amp arent working. I tell him he blew it, by running a 2 ohm load bridged mono on an amp that can only handle a 4 ohm load.

now, lets see if we cna apply this situation to you, lets *assume* you have a 2 ohm load and a 2 channel amp that is only 4 ohm stable mono.

IF you were to have loaded htat mono, the amplifiers woudl see a 2 ohm load, and attempt to give it twice the power its rated for at four ohms. if your amplifier is rated for 800 rms at 4 ohms mono, itll try to produce 1600 watts rms to teh load you put on it. its not a matter of speakers "drawing" power, its hte load they present that tells the amp to produce that much.

so, our poor 800 watt capable amp tries to produce 1600 rms, and realizes hey, I cant do that, ill blow up! so that current draw goes through the fuse, which melts and shuts the amp off to prevent the output transistors from menlting.

fuses dont always work, arent always perfect iun amplifier protection. so if this next one didnt blow, or if we put in a 40 amp fuse instead of a 30 amp fuse, something like that, the next big bass hit, pop! there goes my output transistors.

When this happened with my nice zed tube amp, the amplifier would start up, and go into protection instantly, load or no load. When this happened with an old earthquake 2 channel amplifier, the amp failed to come on at all, protect or not.

So if you can isolate the amplifier and see if it turns on, you can determine whether or not its an amplifier failure, or if there is an issue with your subwoofers, or wiring, or radio.

its gotta be something!

Danman114

UPDATE: got the power to work (it was a broken remote wire, but it is now fixed), now the damn amp is just on ' protect ' and i can't get it off... but here is my equipment:
Kenwood kdc mpv 619 head unit (2-3 yrs old)
rockford fosgate p6002 2 channel amp
and a single infiniti 1030 sub woofer...

i have hooked it up by plugging the sub into the left out put on the sub, and thats putting it in protect mode
i think my friend also tried plugging one into the lefr output on the left speaker out, and the other into the right out of the right speaker out put (hope i explained that right... but that didnt work either... any suggestions... I always thought it was possible to hook only one sub up to a two channel amp... any help is appreciated

Danman114

any suggestions on what to try next?

WhiteRabbit

did you try it without the speaker attached?

does it still start in protect with RCA's unplugged and speaker not hooked up? disconnected at the amp, not at the box or woofer

doubledeuce2k2

iTrader: (20)

yeah, disconnect RCA's, i've had amps ground out through those enough to turn on, but obviously not work. can't check ground too much...