What is wrong with my receiver?

I have an Onkyo reciever which appears to be working with the exception that it produces no sound to the speakers. It was working fine, then the sound just stopped. It powers on and otherwise appears normal.

First, check to see if there is a switch that turns the speakers off. Many receivers have a switch like that so that you can listen with headphones without disturbing people.

There's a possibility that the receiver has an internal fuse that has blown. Since all your channels are dead, it has to be something in common with all of them, such as the power supply. Clearly the power supply is working enough to light up the front panel and make you think the receiver should be working. However, if a fuse is blown that supplies main power to the amplifier board, you will not get any sound. It's possible that there is a circuit breaker on the back panel for this function.

Those are my first two thoughts. The amp probably burned up. Same thing happened to mine. Receivers are notorious for this.. One test is to plug in some headphones.. If you dont hear anything then it is confirmed.

One of two things..

1) FUSE. Every receiver has a fuse inside.. Check to see if its blown, try replacing it but chances are it will blow again.

2) Amp part fried. There is a special part of the receiver that amplifies sound. These die sometimes you wont hear that "click" shortly after turning it on. Usually not worth repairing. If the sound just went off while you were listening, without touching any buttons, then you probably have a blown amp or blown fuse.