Disconnect all speaker connections and rca cables. Leave power, ground and remote wires intact. Try turning on again. If you still have a protection light your amp is faulty. Hopefully you have warranty. Definitely worth repairi .A thumbs up would be greatly appreciated if this answer is helpful to you.

Disconnect the speaker wires then the power and ground completly. Then power up the amp and if the protection light turn on the you have an interanl problem if not then you ohm is problably to low and causing the amp to go into protections.

-david