2 Monoblock Class Ds Not Working, I'm Lost

Amp will no longer turn on

I had got it to turn on and it started making a buzz near the blue outline (louder than the power supply buzz, sounds closer to maybe an arcing?), changed voltage from approx 15 to 14 and it started freaking out so I shut it off. Go to turn it on again, it will try and when it gets close to turning on it starts making the noise again and will not fully power on.

Also is the green the thermistor?


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I think the pulsing of the remote and the input to the protection circuit could be complicating the troubleshooting.

Insert a 10 amp fuse in the B+ line and use the PC supply. You will still need to monitor the temperature of all heatsink mounted components when the amp is powered up.

Does the amp work any differently on the PC supply? Do you still see pulsing on the thermistor?
Going to give an update here

Purchased an in-line fuse, installed it, installed an additional switch on remote wire, and rewired my pc power supply as the extra factory cables were getting annoying and upgraded +12v and ground wires to 14g from whatever was factory
Power supply has issue that it shuts itself off when it powers on an amp (you have to turn it on/off a few times for it to stay on then its completely fine, this works for my x3 4channel but not the xxx, this was occurring before the rewire) my thinking there's an internal current limiter that i have to do some research on if i can find and remove it
I brought in my other XXX amp so now we have a parts amp if needed down the road

Will update again when I get my power supply issue fixed, or I purchase a more powerful variable power supply


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I've had good luck with Pyramid supplies. Astrons are my favorite but expensive. The following is available at parts express but not as cheap. You may be able to find it for less than PE but watch the shipping costs.

I prefer the 100w 2 ohm cylindrical resistors. You can also use them in series/parallel for dummy loads.

The small supply would only connect to ground and remote.
I bought the Tenma power supply it works great
With 10a fuse amp turns on and idles at 5a

FET22, FET23, FET24 get pretty hot at idle, rest don’t get as hot
I’m getting a few whiffs of a smell I don’t like (“magic smoke” similar smell)


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