Onkyo TX-SV717Pro will not come out of standby.

Is it clicking repeatedly?

Mark Z.

Gary,

I have a recollection of a different model from the same era (TX-SV414PRO) that had some 1/4 watt fuse resistors that would open. These were on the main board. Sorry I don't remember the values, but they were under 100 ohms, and I think it was R921,922,923,924. I'd always change all four, and upgrade them to half watters.

Again, I'm recalling from a different model so this may not apply.

Regards, Tim Schwartz Bristol Electronics

I'm pretty sure it does apply. Very similar inside. These models were real "cookers". There was a very involved mod which involved actually cutting away the burned area and adding a daughter board complete with regulators. I never did this mod myself. These units weren't worth it even back then...

Mark Z.

There is no relays clicking and no burnt components or even darkened areas on any pcb. Ive got +13v going out from the pc but nothing coming back on the power line(labeled on ps connector). I found q706 to be bad and replaced it. I get vdd of 2.34vdc into q701 (microprocessor). I also see 5vdc from the power switch shorting to gnd when activated. I do not see anything coming out of the pin labeled power. I am thinking either the IC should have a greater vdd or the chip is bad?

Thanks for any and all help Gary

Gary L. Woodruff wrote:

I can just about guarantee you've missed a large burned area hiding under the big white flat cable which goes from the main board up to the front panel. In this area are several resistors which have been overheated - any one or more could be open. Also there is a common tendency to develop cracks in the board there which actually damage the foil runs causing (again) open circuits. In extreme examples a hole may even be burned in the board.

Look under that big white flat wire...

I have a PDF of the TX-SV525 which is very similar in this area if you need it.

Mark Z.

Mark, Thanks for the tip. I do see the resistors you are speaking of r921, r922, r923 all .47 ohm 1/4 watt. All are good as well as the small rectifier diodes in the same area. There is some slight darkening of the pc board in this area but it is VERY slight. I do not see any voltage on the microprocessor pin labeled POWER when the power button is depressed. This voltage turns on a trans in the power supply feeding ac to the transformers. Shouldn't I at least see some voltage on this pin of the microprocessor?

Thanks, Gary

Mark Zacharias wrote:

The Power pin runs the speaker relay driver. It's not the B+ power for the micro.

I'm looking at the 525 schematic, so the notation may be a little different.

Try looking at Q925, your 5.6 volt regulator. Maybe no DC input to it at all. (cracked circuit board is very common on these - and very hard to see. You'll need a magnifying glass.)

Mark Z.

Mark, Thanks, I do not get anything at q925. I do not get a relay latch in the power supply board rly901 that sends 120v ac to the big power transformer. I believe q922 gets its input v from one of the output windings from this transformer? A couple of possible clues could be that if I disconnect the large ribbon cable from the display to the main board my relays power and I do see 12v out of q925. I did replace q706 on the microprocessor board. I does look like the storage capacitor is open here also and I have not replaced it. I am assuming that this is only for memory storage and will only affect memory storage but the unit still should operate?

Thanks much for your help,

Gary

Well, the output of Q925 may be getting loaded down, but I rather suspect R928 which if I read my crummy PDF correctly is 18 ohms at 1 watt and feeds the input to Q925. Once again don't forget the possibility of a fine crack in the board. Do continuity checks to confirm the integrity of foil traces.

You can e-mail me direct at:

mark snipped-for-privacy@labolgcbs.net

and reverse the domain to read "sbcglobal"

notice there is an underscore _ between my first ande last name.

Do you have the actual schematic? If not I can probably e-mail it to you.

I don't have an actual PDF of this model but I think I have a hard copy - if so I can scan a better copy than I'm looking at right now.

Mark Z.