Yamaha HTR-2067 repair

[ubis]

Hello,
I'm trying to repair Yamaha HTR-2067 receiver. It doesn't turn on, no clicks, nothing.
Now looking at standby power supply schematic



There's nothing on PWR_RY when power button is pressed.
Also I've checked S9, ACDET voltages, and both seems to be higher than it's written on schematic. S9 is about 14V and ACDET is about 9V.
However, looking further:



There's nowhere else S9 is connected, just to an 3.3V regulator. Which makes stable 3.3V voltage for microprocessor(I've checked with scope).
Power button is working fine, traced back to the microprocessor. I've also manually connected relay RY151 from 5V power supply and relay works just fine.
I've also tested output of thermal sensor IC134 LM19, which output is about 1.75V, so temp is not triggering this.

I'm not sure where to look now... One important thing - main power supply caps looks wierd to me, their vents are kinda bloated. Gonna take them out and check ESR.

Full service manual - https://ufile.io/saae8

Edit:
Problem was that microcontroller detected low ac voltage multiple times.
I've managed to get into diagnostic menu, which resets the mcu and now receiver works just fine.
It seems like on these Yamaha's when protection system is activated 3 times in a row, it won't power on anymore, unless in diagnostic mode.

[pae25]

Hey! - Can you let me know how to get into diagnosis mode?

Thank you!

[Chris56000]

Hi!

It's all explained and covered in the HTR–2067 Service Manual which you can get free of charge from Elektrotanya!

(Original Factory PDF with coloured highlighting on power rails of schematics!)

Press the "Tone Control" and "Info" buttons together and hold them in whilst you switch the main power switch on.

If you've got a fault code present, it will be displayed as a "P" code in the front display!

Chris Williams

[mzacharias]

Hi!

It's all explained and covered in the HTR–2067 Service Manual which you can get free of charge from Elektrotanya!

(Original Factory PDF with coloured highlighting on power rails of schematics!)

Press the "Tone Control" and "Info" buttons together and hold them in whilst you switch the main power switch on.

If you've got a fault code present, it will be displayed as a "P" code in the front display!

Chris Williams

In the event of a high-current shut-down, the above procedure will produce only a "click" as the relay cycles once. One would then need to resolve the short circuit. Blown channel, shorted bridge rectifier or main filter cap, etc. Yamaha protection circuits of recent years are so fast the display never comes up. Once the over-current protect has been engaged the receiver will do nothing, except flash the Standby LED when you press the Standby/On button.

I did warranty work for Yamaha for over 20 years.

[basil]

Hi ,

Initially the unit was showing error PS PRT 111L ,as per the service manual [Yamaha HTR 2067] checked the main PCB for a faulty transistor in Main amp board . Now moved to OPE3 .

 OPE3 PCB shows some wearied dc voltages at the output    .

*  S9               46.9 VDC when measure with respect to MGND .
*PWR RY         0Vdc
*ACDET           34.3 VDC


*AC input 249 VAC
*AC output on the sub transformer 18.8 - 0 -18.8 Vac

[mzacharias]

Hi ,

Initially the unit was showing error PS PRT 111L ,as per the service manual [Yamaha HTR 2067] checked the main PCB for a faulty transistor in Main amp board . Now moved to OPE3 .

 OPE3 PCB shows some wearied dc voltages at the output    .

*  S9               46.9 VDC when measure with respect to MGND .
*PWR RY         0Vdc
*ACDET           34.3 VDC


*AC input 249 VAC
*AC output on the sub transformer 18.8 - 0 -18.8 Vac

Are you referring to some other model?

This makes no sense regarding an RX-V2067.

[basil]

Hi ,

No , its HTR 2067 only .

could you review the OPE3 (same as the one givn above ) circuit and let me know is there a small chance to happen like this ?

[mzacharias]

Hi ,

No , its HTR 2067 only .

could you review the OPE3 (same as the one givn above ) circuit and let me know is there a small chance to happen like this ?

I apologize - I was looking at the RX-V2067, not the HTR model which is completely different.

However, your voltage readings make absolutely no sense.

Your reading for S9 cannot, repeat, CAN.NOT. be 46.9 volts with respect to a good chassis ground. (milli-volts perhaps?)

I would suggest re-checking that you have a correct ground reference, or checking that chassis ground is actually chassis ground - some connection to chassis not being made by the circuit board or other connection.

For example - if the rear panel screws are removed you will have no ground reference and errors will occur just for that reason.