Hallo kloehle und willkommen im SONY Forum :smileyhappy:.
Habe Deine Fehlermeldung gegoogelt und es gibt diverse Hinweise und Lösungsversuche. Die meisten in Englisch.
Meistens geht es um einen möglichen Kurzschluss bei den Lautsprecherkabeln oder auch um ein internes Problem. Hab Dir ein paar Antworten angefügt:
Turn off your unit at the power button. Check speaker outputs for a short circuit - also check other end of speaker cables for a short. If you can't find an obvious problem then disconnect all speakers and power up the unit. If all is OK then connect speakers one at a time (this should be done with the unit powered OFF) and power up after each conection. This should identify which output is causing the problem.
If that does not work then it's an internal fault that will require a service engineer to identify - but I hope that is not the case!
I brought the unit to an authorized Sony repair depot and they concluded that all the power transistors were fried. They replaced the system board under warranty (at no charge) and the system has functioned perfectly since.
Generally speaking, an amp attempts to protect itself from heat, shorts, overloads and operator exuberance by refusing to turn on or stay on.
Overloads can be from excessive periods of high output or marginally low impedance loading by the speakers; and shorts would be wiring issues or a speaker blowing up.
You should be able to feel if it's hot. WHY is it overheating? Make sure it has sufficient ventilation on all sides and that vent holes are not blocked by dust balls. Ensure the fan (if equipped) is running as designed (some only operate on demand). Clean dust and debris from it.
If the amp comes back on after cooling, you're lucky. They only have so many self-protection cycles in their lives so continuously resetting or cycling their power without addressing the cause can do more harm than good.
If it protects immediately on a cool power up you should disconnect the speaker connections and try it 'nekkid'. If it comes up then diagnose which lead(s) are shorted. If it does not come up the problem is internal and should be left to an experienced and competent hands-on tech.
Check for loose speaker connections at the speaker as another possible root cause for intermittent shutdown.
