Audio Systems: Yamaha AV receiver power problem, yamaha av receiver, thermal fuse

Question
Hi Robert,

I have a Yamaha AV receiver, RX V630. Not sure what happened, but it started after the cable guy came out to install service over a year ago and plugged the cable box through the receiver's power outlet. Since then, when you hit the power-on/standby button, the unit powers on for all of a 1/2 sec, then shuts off. Hitting the remote or pressing the actual button a few times eventually does the trick–until a month ago, it just wouldn't go on. You press the button, and you hear it clicking, but nothing goes on. (Power dims on the rest of the power strip circuit it's plugged into so I know it's got power to the unit.)

I also popped the lid off the receiver and it sounds like it's coming from the transformer. (If you're facing the back, it's the yellowish large unit on the right.)

I checked Yamaha FAQ but nothing on this except mention of a thermal fuse found on transformers, which I though maybe got blown due to lightening. But, can't find it if that's what it is.

Any ideas before I have to drop this off at the shop? I don't mind replacing the transformer if it's easy to do and if it's not that expensive an item either.

Thanks in advance!

Bill

Answer
Sounds to me like you may have a speaker cable short and have had it for awhile. The receiver was probably trying to protect itself but shutting off after a short period of time. Look closely at the speaker terminals on the back and see if there is even one strand of cable that is long enough to have ever touched the opposite terminal. The possiblities are that: you blew a fuse, blue an output device or the power supply. It could also be one of the capacitors on the power supply. Needless to say if you are not a technician there is little you can do to repair it. You need to take it to an authorized Yamaha service center.