so i have a 3 month old MA audio amp to power my highs. 400w x 2 channel. I blew the 25A fuse and evertime i replace it and connect my power again in blows it. Can anyone help?

 

check your wires make sure nothin is cut or the wire is exposed..like hot touchin metal or the opposite

 

yeh i traced all my power and grounds and everything is fine. i dont even get a second of listening time because as soon as i turn the car on the fuse blows. I've been musicless for a couple days now and its getting old.

 

Try a bigger fuse

 

get a 30 amp..

your pullin 28 now...

and put the fuse in AFTER the power is connected...

that could also blow it

 

I wouldnt get a bigger fuse because that will only harm the amp. Make sure that you check every single connection on the amp.

 

Did you ring out the wires? Test the power wire for continuity to ground....basically using an ohm meter. If there is continuity then somewhere your power wire is touching ground, causing it to short out. As quick as your saying the fuse pops, I doubt it is becuase your overloading the circuit, most fuses will take a little while to pop if overloaded. This sounds more like a 'dead short'. One thing you should do is test your amp itself....could be an internal short as well. First, disconnect the amp completely, and use the continuity tester and place one lead on the power termn, and the other on the ground term, and see if there is continuity internal to the amp. Meaning, something ain't right in the amp itself.

Also, it should say on the amp what size fuse you should use....which depermines the proper wire size...Don't just toss in a larger size until you know for SURE that there isn't a short in the wire somewhere, and that your wire size can HANDLE the larger fuse....Remember, you always want the fuse to be the weakest link in your system, NOT the wire.....

 

The wire can handle it at least for seconds...
2 possible things.. amp is fubar! or grounding out.

Is it the fuse on the power wire or the fuse on the amp blowing?
Check and make sure you dont have the + & - backwards.
Check that there isnt a piece of wire on the amp touching the actual case.
get a multimeter/ohm meter and check the power wire to ground without the
fuse in it.

also make sure the speaker wires arent shorted.. sometimes a couple pieces/threads of wire escape and touch the case.

I had a jbl 1200.1 amp that one day for no apparent reason decided to
ground itself out internally and burn up... it blew a 250amp bench supply fuse...

Rand

 

If this is an inline fuse at the battery or something (ie- not on the amp itself):

Unhook the wire from the amp and leave it disconnected. Insert the fuse like normal. If the fuse blows, then you have a ground fault on your power wire somewhere. If the fuse does not blow, then the problem is clearly the amp itself.


If the problem is narrowed down to the amp:
A) It's broken
B) It draws more than 25 amps normally and you are just undersizing it. There should be a spec on there somewhere or in a manual that says how many amps it draws.

 

the fuse is the one in the amp itself. I traced my power cable and everything is fine there, i checked my ground the best i can in the dark and without taking the back panel out, but i am taking it to my buddy who installs tomorrow. It's a good amp, i hope it just didn't fall to crap

 

anytime the amp fuse blows..the amp is generally done for...
might be repairable.. but it might be cheaper to go ebay.

 

When i first became an installer i upped the fuse by another 10 amps on a radio fuse that was only supposed to be 20 amps. I put a 30 amp fuse in it. The radio wiring harness melted before my eyes when i plugged that fuse in. NEVER up the fuse higher than whats its rated for major problems will come.

 

yeh i figured upping the size of the fuse would be bad.... but back to this speaker theory. If it was caused by the speaker wires wouldn't the amp still get power, but sound just wouldnt develope?

 

Not neccessarily. Depends on a lot of design factors.

Do this, disconnect all the speakers and see if the fuse still blows.

 

well.. the amp's blown. Thanks for the help though

 

I figured thats what would happen. The same thing happened to me a while back.

 

I talked to the guy i bought it from and he still has the sales reciept and the warranty is still valid. I have to call tomorrow.