820-00244 - A1534 2016 Running Slow


New member
Hi !

I hate to work on this board, no fan spin = no fun. The board was liquid damaged, came here with no image. I refurbished the LCD connector that had minor corrosion and replaced the flex, LCD came back. When LCD went back, I discovered there was no KB no TP, the TP flex was damaged so I changed it too and now I have KB and TP, access to session and battery detection & charging.

The last problem is that the Mac is running really slow, I ultrasonic cleaned the board, no change. I tried with another battery and an other LCD, same thing. I found that PPBUS_G3H is a bit higher as expected at 8.75V and it's probably a clue but I don't know how to interpret this.

Thank you for you help and ask me anything that I forgot on this description.


New member
The only thing strange is the "Heatpipe outgoing Air" sensor, which is fun because there is no heatpipe on these...the temp is 128°C. Also it shows me 0.00V on something called "Mainboard S0 Rail", I don't think it makes sense, the Mac wouldn't run if it was the case.


Staff member
Heatpipe temp is irrelevant; I saw it in older machines and doesn't affect.
Should still be corrosion somewhere on the board.
Try to start in diagnostic mode.


New member
Good call diag mode. I have 2 error codes, PFM006 related to the SMC and PPN001 related to the power management. I don't have any SMC for this board to try right now, but if there is crap under the SMC maybe a reballing would be enough. Before, do you have a good board like this to compare some values on SMC and Power IC in diode mode ?