American Bass powers up without remote voltage

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I have an American Bass VFL 200.1 that powers up and power supply section and output section start oscillating with just the B+ and ground connected. I check the remote turn on circuit to see is there may be some way that B+ was bleeding over on the the remote circuit but I read 0 volts at pin 4 of the power supply driver card and that is the pin the remote voltage enters the board.

I’m not sure what is causing this. When I first opened the amp the small 16 volt 22uf SMD cap on the bottom right hand corner of the PWM board was exploded and little bits of metal were laying on the main board. I replaced that cap and checked for damaged components on the power supply PWM board but didn’t find any other issues.

David
 

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