MacBook Air 13 820-00165 no boot


I got a MacBook Air 13 2015, it was a liquid damaged not powering on, there was no charger light indication.
i spotted corroded J6100 connector and remove it also corrosion on U7090 it has been repaired, lcd connector was corroded I also replace it.
MacBook powers on works fine boot to system as it should battery was charging fine, it was working until I screw back main board then it want power on only green orange light no fan spin no boot.
I've removed main board to check why it stopped working and board outside starts booting fine so it looks like there is somewhere corrosion and something looking contact.
I spotted some liquid damage around smc so I reflowed in first place and than only fan spins, no chime no boot, same after reball SMC.
I've checked all voltages from page 57,58 all correct
All termination resistors and traces checked all good
PLT_Reset_L 3.3V
SMC_Reset_L 3.3V
U7100 has been resoldered no changes
U7100 resistance
17-18 point 4 ohm
27-28 point 32ohm
tested on battery only connected, fan spins for a few sec and stop constantly
tested on charger only
Voltage on
L7630 1.08V
L7310 1.8V
L7320 1.8V
pp1v05_s0 1.04V
When I connect SATA HDD to USB it spin but LED is not blinking so no activity on USB.
Any ideas ?
It looks like should boot up according to voltages but its not.
I thinking now maybe BIOS died because of corrosion on Jtag ? It was badly corroded.


Staff member
I suspect bad trace for some SPI resistors.
You can try new BIOS file, just in case.

Can be also corrosion underneath PCH/CPU; heat it with quality flux.


I've tried new bios, duble check all termination resistors and reflow PCH/CPU no results any more ideas? Thanks