Need help working on a ms275

[wooferdog]

This amp was used for a few weeks when new along time ago and put away. It now has a problem. The amp powers on for just a minute with sound then no power to the rails. The green light stay's on and no other lights.I can turn it off and back on after it quit's and get the green light,just no rails. I don't get any output from the pwm out pins #11 and #14. Do I need to replace SG2525A and does this have a new part number ? Thanks

[trickyricky]

What is the voltage of pin 13 and 15? Does it have +/-15v rails (good chance you don't if you don't have the other two rails)? Have you tried flipping the switch by the transformer (the one that lowers or increases the rail voltage...high current/power switch). The SG2535A has not change and is available pretty much anywhere, if you do decide to replace it you don't have to remove the whole board just cut all the legs/pins and desolder each one then clean all the holes and solder the new one from the top.

[wooferdog]

I did power it down and flip the switch a few times but nothing changed. I'll have to check those other pins this weekend and see what they show. Have you ever powered one up after pulling the filter caps still in the sink ? I have done this on all my amps and they wont power on with the caps out. All that I get is the green light flashing but if I put a cap back in just connected to the torrid it powers right up. This amp that I am working on has the green on just like it's ready to run with out the filter caps installed no flashing.