Why does my Behringer B215D speaker comes on then after a few seconds shuts off

SOURCE: I have a B215D Behringer

This should be close to your schematic;

http://elektrotanya.com/behringer_b215a_power-amps_psu_sch.pdf/download.html

Scroll down to "Get Msnusl" link and download. Leaving it on should NOT have caused a failure, however, if it was running and the input was not being driven there may have been feedback going on that did damage. Only thing to do is take it for repair.

SOURCE: Eurolivee B215D - I press

What your amp is doing is going into protection mode. The Class D amplifier topology uses a Pulse width modulation scheme which allows the audio to be modulated onto a generated square wave or pulse train. This is then sent through the MOSFET Driver and then to the High Power MOSFETs that drive the load. The square wave with modulated audio is then filtered by a low pass filter and you are left with your audio. This is great because of the very high efficiency. The downside is that there are more links in the chain to fail. In your case it sounds like one or both of your power MOSFETs are bad and are causing the watchdog circuit to send a shutdown signal to the switching power supply, this is why it is turning off. It is a safety feature to prevent catastrophic failure of the board. (ie. burning the PCB to a crisp) A technician experienced in PCB level troubleshooting shoot be able to repair this for you. Let me know if you need anything good luck.

SOURCE: how do i get parts for behringer b215d my power ic is burn out

Regards, urgent help.

I have a powered speaker Class D, and the PWM isdead. change the IC 3525, is controled by a NE555 which is shutting down. works when connected to a higher voltage 150v, but turned it off, I think by overheating. I already changed mosfets, and ICs. I think that may be some component failure is triggering the protection, someone could help me. I'm a musician and I depend on this car for my livelihood. Thanks