I have 2 amps instalkled in my car one is sony 1200w 2 channel amp for speakers and one is solid audio f2500d for 3 subs my sound and every thing was good but suddenly from yesterday im having trouble when i power on my cd player all my subs make a noise which take much power like all lights of car get dim for 1 or 2 sec and then solid audio goes to protection mode what should i do ?

First disconnect the CD head unit from the sub amp and see if the other amp works. If yes, the problem is the wires to the amp, the amp itself, or the subs/sub wiring. If no, the problem is the head unit--probably an internal short.
If the other amp works with the sub amp disconnected, reconnect the sub amp to the head unit, but disconnect the sub wires from the amp. Try the CD player. If the amp goes to protect with no speaker wires attached, the amp is bad. If the amp is OK, the problem is the subs or sub wires. Hook the wires up to the amp again, but disconnect them from the speakers. Try the player again. If the amp goes to protect, the problem is the amp wiring. If not, the problem is the subs. Check the impedance of each sub using an ohmmeter to determine which amp is out of spec.
Please let me know if you have questions, and thanks for using Fixya.