Onkyo TX-NR353 clicks no display

[kubax]

Hi,

i've got a Onkyo TX-NR535 AV-Receiver that does not power on.

It only clicks and nothin happens. Not even the Display is lit up short.

I can force it to power up "completely" if i remove the power connector to the AMP Board (the one directly from the transofmrator) OR if i unplug the HDMI board from the vertical board (leaving any cables connected)

The vProtection and iProtection both are at 0,5v measured through the vias beneath the CPU and using ground from the P9001 connector

The problem stays even with the preAmp Board removed. I suspect the problem be either on the HDMI Board or the Amp Board, but i can not find any obvious problems.

Any ideas what i could test?

Service Manual:

[kubax]

Re: Onkyo TX-NR353 clicks no display (UPDATE: Check Speaker Wires)

Now i'm a litle bit further, but iritated aswell.

I did try to measure the Power Transistors in circuit, but the readings were strange. So i did unsolder every one of them and measured of circuit.

Here are my measurements.

1:

CE = OL
CB = 13m Ohm
BE = 13m Ohm
Diode Mode B+E- 0.57v, B+C- 0.57v all other combinations OL
2:

CE = OL
CB = 10m Ohm
BE = 11m Ohm
Diode Mode B-E+ 0.56v, B-C+ 0.56v all other combinations OL
3:

CE = OL
CB = 11m Ohm
BE = 11m Ohm
Diode Mode B+E- 0.56v, B+C- 0.56v all other combinations OL
4:

CE = OL
CB = 11.8m Ohm
BE = 12m Ohm
Diode Mode B-E+ 0.56v, B-C+ 0.56v all other combinations OL
5:

CE = OL
CB = 12.9m Ohm
BE = 12.9m Ohm
Diode Mode B+E- 0.58v, B+C- 0.58v all other combinations OL
6:

CE = OL
CB = 13m Ohm
BE = 13m Ohm
Diode Mode B-E+ 0.58v, B-C+ 0.58v all other combinations OL
7:

CE = OL
CB = 9.8m Ohm
BE = 9.8m Ohm
Diode Mode B+E- 0.54v, B+C- 0.55v all other combinations OL
8:

CE = OL
CB = 11.2m Ohm
BE = 11.5m Ohm
Diode Mode B-E+ 0.54v, B-C+ 0.54v all other combinations OL
9:

CE = OL
CB = 9.5m Ohm
BE = 9.5m Ohm
Diode Mode B+E- 0.54v, B+C- 0.54v all other combinations OL
10:

CE = OL
CB = 12.2m Ohm
BE = 12.5m Ohm
Diode Mode B-E+ 0.56v, B-C+ 0.56v all other combinations OL

After testing with every Transistor removed, i got at least some seconds of display before shutting down.

So i soldered every Transistor back on, and did test in between every single one to see if the problem reoccurs... To my complete surprise, it did not go of instantly as before.

I completely rebuild the AV Receiver to see if it changes when everything is in place, including some of the screws to the back plate to have ground distributed to every board.

Now the receiver stated "Check Speaker Wire" the first two times turning it on, and then returns to the previous behaviour of only clicking... I found that resetting the AV Receiver cycles this process.

Now at least i have a Display, but i don't know where to look next -.-

I think the unsoldering of the Transistors did the same as resetting the device with CBL/SAT + Power. It might have done this in the first place, if i would have known the key combination in advance...

Oh, and resetting the device does not seem to work with the pre amp board removed. Wich did led me to think the problem might be there, but the Transistors and foild caps measure good, i think (foil 4nF)

[kubax]

Re: Onkyo TX-NR353 clicks no display

Now i did get it to boot properly, but have no clue why. All i did was measuring the components on the preAMP Board, and putting everything together. I had a speaker connected to Center to test with FM / AM if there is any sound, but did not have any (but i also did not have a antenna). After some seconds i did turn it of and noticed a litle electronic smell... The Power Transistors of the SL channel are hot like hell. although there was no heatsink attached, but to my understanding as there is no speaker connected the transistor should not be powered. the other ones were room temperature.

[madan1]

Re: Onkyo TX-NR353 clicks no display

The power amp transistors are always powered and kept active. Still, it is not normal to get hot without actually producing any output signal.


See service manual - debug mode / service menu.
It will show you why the unit is entering in protection mode ( turning off ).

[kubax]

Re: Onkyo TX-NR353 clicks no display

Ok, the problem is almost fixed.

The problem must be (or must have been?) on the SL part of the AMP board. The two Transistors Q6063 and Q6053 were the ones getting hot, untin they suddenly didn't get hot...

I tested with my multimeter and these two transistors suddenly had close to 0 Ohm resistance. So they are blown.

At first soldering them out didn't fix anything.. no sound but running fine. So i did check a litle on the AMP Board, and found that both Fuses were blown. As i did not have 10A Fuses (or 125v) laying around, i did put in two 250V 5A Fuses until the ones i ordered right now arrive (currently all except food stores are closed because of a pandemic lockdown here in germany).

Trying to play a mp3 from a USB stick, i get sound on every channel except SL, but because of the missing Transistors thats fine, i guess :-DD

I also ordered the two transistors (3 x each) so replace them, and see if the problem reoccurs. I doubt that only the Transistors were bad, but i can not find any other problems in the ciruit for now. At least i have some replacements then

i will report back when the replacements arrive...

[kubax]

Re: Onkyo TX-NR353 clicks no display

Just wanted to report back, the Receiver is working now on all channels.

Replacing the two Transistors fixed the problem. Although i have no idea why they measured ok, but seem to be defective.

Thanks for you help