Yamaha RX-V800 wont turn on

[serafis]

Hi, I'm new to this forum and wondered if there is anyone here who might be able to help me. I have a Yamaha RX-V800 5.1 receiver that won't power on. When I press the power button, the standby relay just clicks but nothing else happens.

Occasionally it did turn on, and I was able to ascertain that there is no DC across output stages, and the diagnostics do not report protection mode.

The standby relay is working, and I have replaced the RAM backup capacitor and most of the components in the standby power supply. I've tried bypassing the relay too, and while the main power supply then gives out the correct voltages, still no action.

It appears that for some reason the power detection circuit is not working, and so is not latching the relay or letting the rest of the circuitry power up.

I've searched this and other forums, and tried most of the troubleshooting suggested.

Some of the voltages on the mainboard are suspect (but I don't know whether theyre measured with it on or in standby!), and I'm now beginning to suspect the microprocessor, but before I chuck it out, wondered if anyone else had had similar problems and perhaps knew where to begin looking.

Thanks,

Serafis.

[GAgola]

Hi,

Did you ever get any help with your unit?

Is there a separate thread dedicated to Amps that switch on and get stuck in the "standby" mode (there ought to be!)

I am having a problem with a TEAC AG-5D that clicks on directly into standby, with the front panel display off. Pressing the standby button briefly powers up the display, which stays on for two, three, maybe five seconds before going off and the unit clicking right back to standby.

During the 2,3, 5 seconds the display is on, all (most?) front panel buttons operate as they would normally. Resetting to factory defaults doesnt seem to help much...

Agola

[serafis]

No, I didn't get any replies. So it's in the cupboard now and I'm on to the next project. I'll use some of the bits for spares one day I expect. Hope you get yours fixed though.

Good luck.

[sakis]

you post a question like that and expect answers ??????

ok i will give you a few

one of the 5.1 outs is gone and protection is activated
secondary psu fault /protection activated
logical fault ( any reason ) protection activated
burned speakers or shorted protection activated ....

and a few million others

in a few words it could be a million things

and also if you are lloking for a fast food solution that will say " go to board B and replace R126 and Q 123 IT WILL NOT COME FROM THIS FORUM !!!!

get a schematic i f you can read it and run a basic test about shorts and voltage ....this will get you somewhere ..... if you can not do that then your one and only option is a yamaha service shop

[yustech]

1 million% agreed.