Yamaha rex-v390 My son's yamaha rx-v390 will not stay turned on and the display is dim. No audio output at all. any suggestions? THX, DP

Hi Rex, what problem or what are you needing from the Yamaha RX-V683
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Regards Franco Dosil

Hola Rex, que problema o que estas necesitando del Yamaha RX-V683
Comenta para as? poder encontrar la mejor respuesta posible
Saludos Franco Dosil

https://usa.yamaha.com/products/audio_visual/av_receivers_amps/rx-v683_u/downloads.html

Sounds like the power transformer is dead. Would have to go in for repair

The problem is with either the Amplifier or the Speakers.

If you disconnect the Speakers and then turn back on and get the same fault then it is the Amplifier.

If it stays on OK then you need to turn off again and connect one Speaker at a time (turning off again between each one) until you find the fault Speaker.

If it is the Amplifier thats faulty then it could be a simple repair that would involve replacing some Capacitors but you would need a Soldering Iron and the knowledge how to de-solder and re-solder components to a PCB.

If you need any further assistance then just ask.

Use Digital FiberOptics to connect them best sound you can get one at radioshack its as simple as pluging it into the back of each device it will not plug in wrong

Does your receiver have any kind of line level audio output? AUX OUT, LINE OUT or similar? If so, you might be able to send that a subwoofer. Most standalone subwoofers have their own crossover and level controls built in, so you can make adjustments there.

Does it display something on LCD? Maybe you have connected speakers with wrong impendance and the receiver is overheating.
Check the impedance of speakers, it should be at least 6 ohm. Also check the receiver manual if it has settings for impendace (6 or 8 ohm).

protection is turned on,it is a seriously damaged,only service can fix it.Probably output transistors are defect,one or more

I suggest you run self diag.  press [FM/AM] key + [Input mode] key and press the [power/standby] switch.

ps prt = power supply problem
dc prt = shorted output or leakly cap in channel
tmp prt means to hot on heatsink

you'll likely have to measure the resistances of the output FETs to find a short, 

Try reseting the Yamaha-Shut the power off, and while holding down presets 1,2 and 3 press power on.