Audio Amps

Are they 8Ω speakers? Before it's reset, it would be a good idea to look at the resistance of the cable and speaker, as the amplifier sees it, otherwise it might do it again.

It might be using one of those miniature, resettable breakers. It's usually rectangular shaped with a long, red button sticking out of the top:

Some fuses even look like capacitors:

Oh! Before I close this:

images courtesy of RS Components

I don't think that you can reset it.You may have shorted the amp. while hooking it up.Most amps. enter the protection status when a component(s) has shorted or if over-heated.You have to repair it.

dawit.

I have designed and built many car audio systems in my day and dealt with many used components. First off, there should not be any issues with a breaker or fuse because the amp would not power up at all and you would not be able to get the protection light on, unless the protection light is on and the power light is not on. The protection light is usually for overcurrent protection. Try disconnecting your speakers and see if the amp powers up without the protection light coming on. If it does then you have a short down stream of the amp. You will need to check everything to find the short starting with the configuration. If you wired the speakers incorrectly it is easy to make this happen. You need to know if you are running mono or stereo and if the amp needs to be in bridged mode for the mono setup. There is also sometimes a switch to put the amp in bridged mode or it does it automatically. If you are in a bridged mode make sure you are wired into the correct leads and it varies between manufacturers. Make sure you are not trying to run too many speakers on the amp by checking the impedence rating on the amp and calculating your sub impedence. If everything checks out you could have a short in the speaker wires or a sub is shorted (blown).