820-00165 strange issue

[tlough75]

So I have yet another 820-00165 that posts to flashing ? has PM_SLP_S4_L but PPBUS is 8.18V. WHat the heck is going on here? This board has been messed with by someone else a little.

 

[2informaticos]

If you get flashing "?" sign, do not bother with power on sequence anymore.
You may have SSD issue, bad traces/connector, APFS issue...

SSD problem is not related with wrong PPBUS_G3H voltage.
I suppose you've posted that voltage without battery connected.
You should check battery bus, for this issue.
May be caused by bad SMC also.