820-00239 Not turning On, no signs of liquid

[phuketmymac]

The customer brought us her MacBook Pro 13" Touchbar from 2016, not turning on.

She said the computer was working fine yesterday when suddenly it did shutdown.
History of that computer: Mainboard (HD says the customer) was replaced. She lost all her data. So I assume mainboard was replaced.

Under the microscope, the mainboard perfectly fine. Only I could notice some solder balls next to D3302.
Rails presents are all the S5 rails, PPBUS_G3H and PP3V3_G3H.

We are getting PM_SLP_S5_L but not PM_SLP_S4_L.
However PM_SLP_SUS_L is bumping...

Following this, we've found out that PM_SYSRST_L was also bumping...

The only chip which seems overheating is the PMIC U7800.

Any idea what we could check next please?

 

[phuketmymac]

Actually we've found PP3V3_PMICLDO to be shorted.
Since the PMIC is getting hot, I believe I should not chase any capacitor on this line right?!

Is the PMIC a painful replacement or straight forward?

 

[phuketmymac]

Chip name is SN650839. Where to find that chip please?

 

[dukefawks]

PMIC may be getting hot because it is trying to supply 3V to the shorted line. Inject 3V and see if any of the caps on that line get hot.

 

[phuketmymac]

Too bad.I won't be able to try that.
Customer got the computer back cause she couldn't wait.

+ she already complained to Apple and will get a new LB since this replaced one failed after 6 months...

I did however spread some alcohol on the caps at the time but none would make alcohol evaporate. I might have missed it though, can't be sure...

Thanks for your help anyway.