Yamaha RX-V2400 not turning on or doing anything

[imito]

Picked up a non-working Yamaha RX-V2400 that is dead. Unit does not power up or make any relay clicks of any kind. Fuses are all good. Suspecting a problem in the standby power board, pulled the service manual and need some help as to which pins should be checked for voltage. So far verified pin PDD on standby board has the required 4.6volts and the relay (RY1) seems to have a working coil. Any help is appreciated.

 

[ramussons]

verified pin PDD on standby board has the required 4.6volts and the relay (RY1)

Now, most of us will have no idea about pin PDD or Relay RY1.
How about a schematic that you are referring to.

 

[Ylli]

Confirm +8.5 volts on the emitter of Q1 (or anywhere along that path). Then confirm the base of Q6 goes high (>0.5V) when you try to turn it on.

 

[imito]

Thanks for the reply!

I didn’t check voltage right at base of Q1 but did check at the S9 pin and it is 11.2 volts.

Base of Q6 does go high briefly when power button is pressed.

Q6 was bad and D11 was shorted. Replaced them and unit now does power up for couple seconds then shuts off. Its not giving any type of protect error and I dont suspect any issue with the amplifier section at this time.