A1708 randomly crashing when battery connected

chedda

New member
Hi,

This board will randomly crash when the cable at J6951 is connected. It will happen during boot or when MacOS is fully loaded.
During boot, for a split second the apple logo will sometimes have a red square background and the loading bar becomes green.
The it will go into boot loop or get stuck not turning on at all.
When J6951 is not connected (no battery power), it seems to run fine.
SYS_DETECT_L is 0.02V, SMBUS_SMC_5_G3G_SCL and .._SDA are both 3.38V, no shorts to ground.
Putting the logic board in another topcase shows same symptoms.
Also tried another SSD and external drive.
Owner says it happened after OS update. Then he changed the SSD and it was fine for 3 days. Has been showing these symptoms since.
 

chedda

New member
So I flashed the BIOS with a cleaned ME I found at win-raid forum, but it's still showing same behaviour.
All others images I tried from other websites either don't turn on at all or get stuck during boot screen.
Do you have image(s) i could try?
Maybe it's a HW issue after all? What could I check?
 

chedda

New member
No, but i will, once re-install finishes (can do while battery disconnected).
It's a 820-00840-A EMC 3164.
 

chedda

New member
It crashes in safe mode and with the image you provided.
I can only bypass SMC if i disconnect battery (J6951). It's taking awfully long, though...still loading.
But I'm not sure how this will help as the board will only crash when J6951 is connected.
 

chedda

New member
In bypass mode, the progress bar is at around the middle and hasn't been moving for 20 minutes now.
 

chedda

New member
I tried installing via Boot Camp. After restart, it tries to boot into the Windows Installer, but gives ACPI_BIOS_ERROR right at the beginning.
I did this all while J6951 is disconnected.
 

2informaticos

Administrator
Staff member
Depends on the heat applied to CPU.
Check first for knocked off components (both sides of board) and be sure to have good solders.
 

chedda

New member
i needed lots of heat to get them off, because the heat sink was still. maybe i should have removed it.
PPVCCCPU is 0.95 initially, then drops to 0.
 

2informaticos

Administrator
Staff member
Pufff, heatsink must be always removed, when apply heat near CPU.
The heatsink maintained the CPU die with high temps for long time and pressure could damaged it also.
 
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