820-00281 Was not Turning On, Now Does Not Turn Off (Gives KP)

brunomotter

Member
Hi all! First I'm glad I'm now part of this forum. The issue is with an 820-00281 board here. Initially it was not turning on. I figured out that the battery was bad and C4403 was shorted to GND. I replaced that cap and the board turned on without battery. I ordered a new battery and installed it on the machine. Now the machine boots, charges battery and works like a charm, but whenever I try to put it to sleep or try to turn it off it gives me a Kernel Panic related to ACPI. I am new to Touchbars and have worked on only a few boards of this kind and am completely lost without any ideas on where to start troubleshooting this issue. If anyone have ever seen something like this before it would be great help! PS.: I already tried to test without battery and with an original battery(another machine of the same kind arrived here) and the issue persists! Kernel Panic on ACPI everytime when trying to shutdown or sleep.
 

2informaticos

Administrator
Staff member
Did you try USB test OSX?
Discard firtst a software issue.
Also start the board with minimal peripherals; use USB keyboard/mouse, no touchbar.
 

brunomotter

Member
Did you try USB test OSX?
Discard firtst a software issue.
Also start the board with minimal peripherals; use USB keyboard/mouse, no touchbar.
I made a clean OS install... Software was my first guess as it's often software related on those cases... I will try disconnecting everything to see if it works, but I doubt it because I put the board into another case and the problem persists... This issue is really odd!
 

brunomotter

Member
Well... Tried with everything disconnected but display and the problem persists... Tried again in the other case and the same occurs... KP every time I try to put the machine to sleep or try to shut it down!
 

dukefawks

Administrator
Could be anything. Corrosion under SMC or WiFi module is something to look at first. It all depends on where the liquid damage originally was.
 

brunomotter

Member
Could be anything. Corrosion under SMC or WiFi module is something to look at first. It all depends on where the liquid damage originally was.
There was light corrosion near C4403, but just in that area. The rest of the board looks really clean!
 

brunomotter

Member
When I arrive at my store today I'll copy/paste the Kernel Panic report here to see if someone has any idea on what to look.
 

brunomotter

Member
Reflowed SMC. Same thing... U3730 has underfill, and besides, wifi works perfectly, so does bluetooth and that area looks really clean, no corrosion at all! I don't believe it has anything to do with the problem, but it may be(and probably is) a bad SMC though... I will have to buy the stencil for it
 

brunomotter

Member
I ordered the SMC stencil for this model, waiting for it to arrive from China... Will take some time! Any other ideas on where to look? I went back to the place where the capacitor was shorted and tried reflowing U4200 as I thought maybe I had damaged the BGA solder while heating up the area to remove the shorted cap(C4403), but no luck, same thing! The machine boots fine(a little slower than normal but boots ok) and works perfectly until I try to put it to sleep or turn it off... Any of those two things make the machine give a KP related to SMC kext as seen here:

*** Panic Report ***

panic(cpu 0 caller 0xffffff7f8b34cfb0): "ACPI: Fatal opcode executed in \_PTS. Type = 0x01 Code = 0x00004d38 Arg = 0x00000000."@/BuildRoot/Library/Caches/com.apple.xbs/Sources/AppleACPIPlatform/AppleACPIPlatform-298.250.5/ACPICA/source/os_specific/service_layers/osdarwin.c:1568

Backtrace (CPU 0), Frame : Return Address

0xffffff9221173730 : 0xffffff80085af82d

0xffffff9221173780 : 0xffffff80086eb795

0xffffff92211737c0 : 0xffffff80086dcf4a

0xffffff9221173830 : 0xffffff800855cae0

0xffffff9221173850 : 0xffffff80085af247

0xffffff9221173970 : 0xffffff80085af093

0xffffff92211739e0 : 0xffffff7f8b34cfb0

0xffffff92211739f0 : 0xffffff7f8b36df7c

0xffffff9221173a10 : 0xffffff7f8b35c946

0xffffff9221173a60 : 0xffffff7f8b37db51

0xffffff9221173ae0 : 0xffffff7f8b37f2b6

0xffffff9221173b20 : 0xffffff7f8b37ff7a

0xffffff9221173b70 : 0xffffff7f8b3774fd

0xffffff9221173bb0 : 0xffffff7f8b37bc56

0xffffff9221173c10 : 0xffffff7f8b374bba

0xffffff9221173c60 : 0xffffff7f8b33aa7e

0xffffff9221173c90 : 0xffffff7f89490e59

0xffffff9221173ce0 : 0xffffff8008c7a345

0xffffff9221173d20 : 0xffffff80086e1fe2

0xffffff9221173d30 : 0xffffff8008ad1815

0xffffff9221173df0 : 0xffffff8008aea1df

0xffffff9221173f40 : 0xffffff8008bbb0ed

0xffffff9221173fa0 : 0xffffff800855d2a6

Kernel Extensions in backtrace:

com.apple.driver.AppleSMC(3.1.9)[EA40681F-C45F-30F4-B308-B20D12A24493]@0xffffff7f8948b000->0xffffff7f894a8fff

dependency: com.apple.iokit.IOACPIFamily(1.4)[3D873DDA-8201-3402-B176-ADA3D6BC5572]@0xffffff7f89482000

dependency: com.apple.iokit.IOPCIFamily(2.9)[6EC56853-DB65-393D-B7F0-D1B15D77E97B]@0xffffff7f88e95000

com.apple.driver.AppleACPIPlatform(6.1)[AB69644B-CE2E-3C6C-8FC4-E1BC05F6F705]@0xffffff7f8b32e000->0xffffff7f8b3c9fff

dependency: com.apple.iokit.IOACPIFamily(1.4)[3D873DDA-8201-3402-B176-ADA3D6BC5572]@0xffffff7f89482000

dependency: com.apple.iokit.IOPCIFamily(2.9)[6EC56853-DB65-393D-B7F0-D1B15D77E97B]@0xffffff7f88e95000

dependency: com.apple.driver.AppleSMC(3.1.9)[EA40681F-C45F-30F4-B308-B20D12A24493]@0xffffff7f8948b000


I made a clean install of MacOS High Sierra again for precaution(was running a clean copy of Mojave 10.14.5 before) and same results, so this is not software related for sure!
 
Last edited:

brunomotter

Member
I'm almost sure this is a SMC issue, as the KP log says its kext is in backtrace. Anything else I can try before the stencil arrives?
 
Top