Protection light come on before amp is turn on it stays on for four seconds and then the amp turns on

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. Time to get an old school Opti Drive. .A thumbs up would be greatly appreciated if this answer is helpful to you. Lanzar

This is a short or unstable ohm load. Remove all speaker wire connections to see if the amp will stay on.
If the problem goes away when disconnecting the speaker wires try this:
1) Check volume level on zone one and zone 2 if connected. If it is too high the amp will go into protect mode and shut off exactly as you described.
2) Make sure no wires are touching any other wire or the metal surface of the amp. This will cause a short and send the amp into protect mode.

Double check the ground wire to make sure it is grounded to an unpainted surface of the car. Otherwise turn cd player bass down and amp gain at no more than 3/4

perhaps you are pushing the amp to hard check that the gain control knob is not turned all the way up. This will cause the amp to overheat. If not that check all of the wiring to the amp for a possible short.

Disconnect any speaker from the amp then re-power. If it still goes into protection, your amp needs serviced. Shorted output transistors most likely. And check your Sub for shorts as well. If the voicecoil on the sub is burnt, it will short any amp. If you can use a meter, check the resistance on the sub. Hope this helps

Looks like you have covered all the basics.

The remote wire is the switch that turns the amp on and off. So you are probably just killing the power to the amp.

Sounds like a short in the amp itself if all the input and output wires are disconnected and the protection is still coming on.

It appears that the amp is going into protect mode. To eliminate external causes, read through the following page. Let me know if you have any other questions.

Amp in Protect Mode - Troubleshooting

It sounds like you have a broken connection in the amplifier. The first thing to check is the fuse. Sometimes the contacts become weak on the fuse holder and the connection becomes intermittent. Any other troubleshooting would require opening up the amp. Any repairs would require resoldering the broken connection.

Let me know if you have any other questions.

Disconnect all speaker wires from the speaker terminals of the amp and disconnect signal cables from the amp. If it powers up, the wiring needs to be checked. If the protect light remains on, the amp likely has blown output transistors.

Theres a short in the ground connection