Badcaps.net Forum
Go Back   Badcaps Forums > Troubleshooting Hardware & Devices and Electronics Theory > Troubleshooting Laptops, Portable, and Mobile Devices
Register FAQ Calendar Search Today's Posts Mark Forums Read

 
Thread Tools Display Modes
Old 11-26-2020, 02:40 AM   #1
myth77
Senior Member
 
Join Date: Feb 2017
City & State: Split
My Country: Croatia
I'm a: Knowledge Seeker
Posts: 168
Default Macbook air 2017 damaged not powering

I didnt repair macbooks before...

To cut long story short...my nephews were playing and one of them landed on the macbook on the couch the macbook was not working and it was pretty curved when i got it...

So they ask me to take a look...i disassemble it completely...check the board and found two coils broken from the pads...and resolder them.

When i plug the charger it goes green two seconds then orange light.
Tried to power it (short R5116) ...but nothing...so i downloaded schematic...first i checked for short to ground but couldnt find any then i checked always present rails and i have all except last two. So:

PPBUS_G3H, PPBUS_S5_HS_COMPUTING_ISNS, PPBUS_S5_HS_OTHER_ISNS, PPDCIN_G3H_ISOL, PPDCIN_G3H, PP3V42_G3H, PPVRTC_G3H, PP5V_S5 all these rails are ok, voltage present.

No voltage on rails PP5V_S4RS3 and PP5V_S0. The resistence on the PP5V_S0 is around 63 kohm but on PP5V_S4RS3 is not stable...its rising indefinitely.

I am not sure do i need a working battery to start it? i think its broken..but not sure...i left it overnight to charge but when i check it in the morning (without charger) the voltage on PPVBAT_G3H_CONN were 2,3 volt and droping. When charger and battery are plugged together i can read on PPVBAT_G3H_CONN connector somewhere arround 0,2 volt then jumps like 0,89v, 1,7v, 2,3v then back on around 0,2 volt and even lower.

So, i think i covered everything in description, please advice where to look?

Last edited by myth77; 11-26-2020 at 02:42 AM..
myth77 is offline   Reply With Quote
Old 11-26-2020, 07:04 AM   #2
piernov
Moderator
 
Join Date: Jan 2016
City & State: Valbonne, 06
My Country: France
I'm a: Knowledge Seeker
Posts: 2,762
Default Re: Macbook air 2017 damaged not powering

Power sequence always goes G3H → S5 → SUS → S4 → S3 → S0 → VCore. Go through the list of power rails measuring their voltage in that order.
You don't need the battery to be plugged in, but you have to use a genuine Apple Magsafe2.
__________________
OpenBoardview http://openboardview.org | IRC #[email protected]
piernov is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



Badcaps.net Technical Forums 2003 - 2021
Powered by vBulletin ®
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
All times are GMT -6. The time now is 02:46 PM.
Did you find this forum helpful?