820-00165 intermittent boot sleep issue

[MegaObi]

Strange. No sign of liquid or drop damage

Customer says it occassionally doesn't boot
Soemtimes don't wake up from sleep
occasionally wakes up to prohibiting sign.

I suspected ssd so i try to boot from external USB. It didn't work.

I tried another good working ssd it booted to osx
I tried external USB again and it booted to osx
I then tried original ssd and it booted to osx this time.

Where is good point to start?
Test all voltages?

I noticed also when I boot to recovery and check terminal date was incorrect also?

 

[2informaticos]

So it doesn't boot always from USB?
Do yo always get chime?

PRAM done?

Can you always acces boot menu?
Even if you only get network option...

 

[MegaObi]

It doesn't always boot from USB and sad
always chime

Pram done

Can always access boot menu

Sometimes takes veryyy long to boot.

 

[MegaObi]

AHA! u8005 got fluff around it very hard to see.. could this be the cause for all these issues?

 

[2informaticos]

Could be, as it is a PCH power supply.
Change it and check its output (1.05V at pins 5/7).

 

[MegaObi]

nice. all done working great now. thanks informaticos!!