Yamaha RX-V383 powers on and goes into protection mode

[lifemikey]

Hi,

I have a Yamaha RX-V383. After a power outage I tried to turn on the amplifier a week ago and it goes straight into protection mode and does not show anything on the screen.
I tried the Tone Control+Info+Power to run diagnostics mode and it made a sound through the speakers like it was trying to do diagnostics and then went into protection mode. I tried again to run diagnostics mode and cannot it goes straight into protection mode.

I opened it up and looked for signs of wear and don't see any.
Any ideas on how to start troubleshooting?

Service Manual is located at elektrotanya.com/yamaha_rx-v383_htr-3071_sm.pdf/download.html

 

[D.A.(Tony)Stewart]

It could be anything from insufficient solder to a microshort to ...
Start measuring all the DCDC voltages p90/132 and look for current sensing circuits.

 

[BradtheRad]

A blackout (and servicemen solving it) can cause harmful voltages to enter your equipment. Did lightning strike your house or nearby? Can you measure your house voltage to make sure it's normal?

Can you test the power supply voltage inside your equipment to see if it's normal according to the service manual?

Suppose you try disconnecting the speakers. Do you hear anything through headphones instead? And do your speakers work okay with a different amplifier?

 

[lifemikey]

The power outage wasn't related to lighting.
I had it plugged into a surge protector so I thought that would protect it...
The display doesn't even turn on just the initial click when the power button is turned on then the red protection light.

I have Ting and all it detected was a power outage and then power restored. No abnormal voltages.

I'll try testing the power supply voltage