Question about Rockford Fosgate p-450.4 Car Audio Amplifier

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Amp blowing fuses

I have a punch p450.4 amp and I was driving and the my music stopped. I saw that the protct light was on and when I restarted the car the power light was on but just cracky sound. When turned up, the amp goes into protect mode. I removed the stereo a pioneer avic d3 everything was good. I unhooked one rca, it touched nothing, sound came back, and then the amp blew the fuses. now, with the correct fuses replaced everytime the amp goes to power up it blows both fuses. I am thinking it has an internal short?

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Re: amp blowing fuses

The amplifier probably has shorted output transistors.

Disconnect the speakers and RCA cables. Replace the fuses with two 10 amp fuses or a single 20 amp fuse. If the amp blows the fuse when it powers up, the outputs are almost certainly the problem. Don't try it with the two 30 amp fuses. The smaller fuses will provide more protection for the power supply. If the amp powers up with the smaller fuses and they don't blow, check the speakers and the wiring (for shorts to ground or shorts between wires).

Posted on Nov 22, 2007

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I used to have one of those amps also (nice amp btw) Did you try another fuse of the same size?
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Just currious but what size fuse do you have connected at the battery?

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