My amp has power but then immediately goes red into protect mode.
Ok, being an old-school "back yard" installer when i began, gave me 2 immediate possible diagnosis for your problem. I was running a Kicker zx550.3 amp to 2 Polk DB 12'inch Subs rated 600w max 1500w. I also used a LOC converter (Line Output Converter) in order to use my stock Bose stereo since it did not have RCA outputs. Now shortly after running this setup (approx 2 weeks) I noticed a substantial drop in sound output and also noticed some ground noise/distortion coming thru the subs. After tracing my wires that connected my LOC to the Amp, and Rear Speaker Wires of my Radio to the LOC, I noticed that by jostling the wires there was a connection issue. If you are using your factory radio to power your regular component speakers (tweeters, coax, mids) then chances are your stereo feeds into a FACTORY INSTALLED amplifier. If thats the case, then you need to access a Wiring Diagram for the Harness coming off the Factory Amplifier! Once this is viewable, check the wiring and locate the "Amplifier to Radio Signal Wires" and also the "Amplifier to Speakers Signal Wires" ... Now go back to your LOC and look at the wires you tapped to get the Line Signals to the converter, and make sure that you havent tapped your lines off of the AMPLIFIER TO SPEAKER wires. These wires carry a small electrical current because they are coming powered from the Amplifier, and most Line Output Converters are PASSIVE, which could short the signal the LOC creates thus reducing your signal gain, but does have the capability to surge back to the Factory Amplifier, which could possibly melt the shielding of the factory wiring, and thus allow your signal to cross or ground out! If you can, try running another RCA input to your Sub-Amplifier from another source other than your car, and see if your protection lights go out and the amp returns to normal operation. If so then your LOC or Factory amp is to blame. If not, then the second diagnosis is much simpler, which is your Alternator current has been reduced due to many different possibilities, and you should acquire a .5 or 1 Farad Stiffening Capacitor which will reduce the excess draw from your charging system. But due to the first solution being my problem exactly, im willing to bet your's lies along the same variables... GL to you!