My amp keep jumping in an out of protect

Power up the ampwith no speaker connected. If it goes into protect mode, the amp has been damaged.
If it is OK, check your user manual for wiring instructions, loading etc.
Do not allow the speaker wires to touch the car chassis/metalwork!

Be aware your amp can deliver more power to a 2 Ohm speaker, but will not work if the 2 Ohm speaker somewhere in the audio spectrum comes beneath the 2 Ohm. Because you want the sub, to go as low as possible, it could be the speaker will have a very low impedance under 20 Hz, causing your amp to go in protection.
The power you give to the amp, will not be the cause it going in protection. It is sensing the output current, so it will stay in the borders the end stage can deliver. Try two speakers in series and give the same power. If the amp is not driven into the protection, I think you are closing in to what is causing the problem.

If you disconnect your speakers and input and the problems remain it means you've blown your end-stage and the amp needs repair.

if the problem disappears when disconnecting the speakers you may want to check if the impedance of your speakers is within tolerance of the amp.

Ok check the remote wire running from the headunit to the amp should be giving v12 feed whiles headunit is on.

check or change grounding position.

take cover off the amp as the circuit may be over heating.

check it without the speakers if they go to protection,and if not check the speakers

try hooking up only the power ground and remote see what happens if protection light is on then u have a problem with amp if it goes off then hook up rca if still off then hook up speaker wire if it turns on then u have a prob with speakers

check your amp and speakers and make sure their both hooked up 4 ohm instead of 2 ohm because if you have 1 set of voice coils on your speakers they can only be hooked up four ohm and not bridged to your amp because if you keep trying this you will lock up your speakers if the speakers are only 4 ohm than just hook them up regular to each channel on your amp if your trying to brigde four ohm speakers to your amp it will keep going into protect or worst case scenario you will fry your speakers and you can check your ohm with a ohmmeter trust me my brother owns a stereo shop

Two things, a problem with the speakers, or the amp is toast. If there is a short is the speaker, wire touching, bad voice coil, the amp will go into protect. I have also seen many, many MTX amps that go bad, and just stay in protect. the easiest way to check, is to unhook the speaker wire from the amp, then power it up, if it still goes into protect without a speaker hooked to it, you have a bad amp. Hope this helps.

Having the speaker wires hooked up backwords will not cause protect mode. If the wires were crossed (in other words shorted), that would. Disconnect all speaker wires, if the unit is still in protect mode, than the output transistors are probably shorted and the unit will again require service. Upon return from service, I would turn on the unit without speakers to insure that the unit at least works that far. Also, if you have an ohmmeter, measure across the speaker terminals. You should read either 3 or 6 ohms. If you read 0, the problem is a shorted speaker that then shorted the amp.

Keep us posted.
Dan

Best thing to do is disconnect all the speakers with no input on the amp turn it on and if its still in protection seek help in the repair of said amp at http://performanceteknique.com.. If the protection light goes out then start to put back on each speaker with no volume and the unit off. if you get to a speaker that makes the unit go into protect then leave on that speaker and disconnect all the rest .. If the protect remains then something with that speaker or wiring is bad BUT if after disconnecting the rest of the speakers that you hooked up then theres is still a power issue with your amp