AV Receiver turns on for a second, then turns off

[nige838]

I have a Onkyo AV Receiver model HT-R8230. It turns on for a second, then goes into safe mode (unit turns off, then the standby light blinks). I've spent the last several hours searching for information, with nothing to show. I have checked the fuses, all good. I have carefully inspected the components, all appear to be ok. I have checked the rectified voltage, 47v, ok.

I'm curious if anybody has any ideas or direction. This Receiver sounds really good, otherwise I'd just part it out...

I've repaired 2 units before this one, both from the '70s, so I have some idea of what I'm doing...

Any help and direction would be greatly appreciated...

Thanks,
Nick

 

[c2cthomas]

The owner manual sez that the protection circuit has kicked in and to take it to a service center.

Lot's of things can trip up a protection circuit - shorted speaker wires - shorted speakers being the most common. Disconnect the speaker wires at the units terminals and see if it fires up. If it does then check your wiring and speakers for shorts.
After that it's usually as sign of blown output xsistors and/or something near them (usually a cap or diode shorted to ground or Vcc). Seeing how the fuses are not blowing it looks as if something has "opened" rather than shorted.

http://support.radioshack.com/manuals/ome31-5037.pdf