Yamaha RX-497 turn off after 10-15 min

[coojoe_213]

Hi all. I have this receiver, but after 10 min turn off.
I check the DC/PS values, and i see PS values are low. The normal values in service manual are DC:19-51, PS:54-84 . My DC is perfect 035, but my PS is...(my values are 53/52/51....47/46), every 5-10 second they are low. I check all electrolic capacitors in Power supply, but the are fine. C254 (22nf/650v) is 15nf when i check with my multimeter. Is this may be a problem or no? Can you tell what to try? :/


EDIT: Now, receiver turn off after 1 minute.

[Chungalin]

Re: Yamaha RX-497 turn off after 10-15 min

If it turns off after some time, then it means that it turns off when something heats up. You can leave it in a cold environment and then heat with a heat gun (at about 150ºC) all suspicious circuits until you detect one component (or a group) that is more sensible to heat and speeds up the turn off process. 22nF film cap is a known culprit in these models, but symptom is different: it doesn’t turn on, it appears dead. And this is not your case. Yet.

[budm]

Re: Yamaha RX-497 turn off after 10-15 min

I would change that 22nF if it is only showing 15nF, that is way off the tolerance.

[Volvos60d5]

Re: Yamaha RX-497 turn off after 10-15 min

My YAMAHA RX-497 is dead, and doesn't powers up. I replaced C254 with a new 22nF cap and it is powering up again. Thx.