Macbook Air A2179 Logic Board Component Find

[sergy61]

Hi All,
I have a macbook air 2020 which has a problem in logic board. I have seen that two components blown and probably that's why camera and keyboard back light not working. Can you help me to Identify these parts because there is no board view only partial boardview available and i could not determine them.

It is around U8500 but i could not be sure about them.

By the way, laptop working normal except camera and backlight issue.

Thank in advance.

[mon2]

Re: Macbook Air A2179 Logic Board Component Find

1) Please see attached.

2) check Backlight fuse @ F8400. This should be the same as PPBUS_G3H.

3) voltage @ backlight rail, L8410 - pin 2 ?

[sergy61]

Re: Macbook Air A2179 Logic Board Component Find

1) Please see attached.

2) check Backlight fuse @ F8400. This should be the same as PPBUS_G3H.

3) voltage @ backlight rail, L8410 - pin 2 ?

Thank you very much for your answer. Actually LCD backlight is working however my problem now only with keyboard backlight and camera. I thought that it could be because of these two blown component. Are there any other reason for that?

Also for CC774 i could not find 3pF 25 V capacitor in germany. c0g 0201. What do you think to use 3.3 pF instead of this?

[mon2]

Re: Macbook Air A2179 Logic Board Component Find

Yes, 3.3pf will be fine. Let me check the schematic in about an hour and write back. Check the keyboard connector and cable to be sure there is no liquid damage. It worked before?

Also, Arrow should have the caps and common parts.

[mon2]

Re: Macbook Air A2179 Logic Board Component Find

1) The 3pf cap @ CC774 is not required and will not impact the operation of your logic board. These are filter caps to ideally stop certain frequencies from leaking out of the logic board so they do not affect over the air radio / TV / WIFI / BLE channels. You will not miss this cap if it is damaged.

2) What is the voltage reading on L6520, pin # 2? Black meter lead to ground; red on pin # 2 of L6520; meter in DC volts mode.

Do you see a high voltage of 25V or higher ?

[Rayskate]

Re: Macbook Air A2179 Logic Board Component Find

I have a similar problem with my Macbook air A2179 2020, But I think the U8500 is bad also because when I found the L8570 it was welded to the board and the trace is now gone (On the PP5V_G3S SIDE) I pulled one off a old MBP board I had and jumped it to the cap below in the same rail thinking that it would fix it, but it didn't work. Do you know the actual part number for U8500, so I can order one from somewhere or know if it might be on a older MBP? Any help would be appreciated.

[mon2]

Re: Macbook Air A2179 Logic Board Component Find

See attached.

U8500 on the A2179 (820-01055) schematic is:

Silego part # SLG5AP1443V

This is a load switch (aka solid state switch / relay).

If you are in a rush, you should be able to purchase this from Louis's Rossmann's webstore in NY.

Otherwise,

https://www.aliexpress.com/w/wholesale-slg5ap1443v.html

Do confirm that this is a faulty part before going down the wrong rabbit hole.

Check the voltage to ground for the following pins on this load switch:

PP5V_S0_LCD ; to confirm this IC is being powered
PANEL_P5V_EN ; to confirm this load switch is being enabled
PP5V_S0SW_LCD ; to confirm the voltage is being passed if enabled

[Rayskate]

Re: Macbook Air A2179 Logic Board Component Find

I confirmed the 3 lies were getting proper power and decided it was ok to make a bridge from L8570 to CC774 and CC775 on the PP5V_G3S rail. Pretty confident and getting the proper voltage. I put it back together and there was still no keyboard backlight or camera. So I took it apart again and desloderd L8570 and CC774 found another trace gone and no longer getting power to CC775 either. I am thinking about running a jumper from R7401 but not confident with that idea. Maybe I should remove U8500 to see it it has traces missing also now.

[mon2]

Re: Macbook Air A2179 Logic Board Component Find

There are other caps on this pp5v_g3s. Are they receiving the correct voltage?

The single cap at cc775 will not be missed and will not halt the operation. Skip it if others are ok.

Have you inspected your keyboard / trackpad cable?

Keyboard works otherwise?

Is the keyboard the original or a replacement? Not every keyboard replacement is with a backlight.

[Rayskate]

Re: Macbook Air A2179 Logic Board Component Find

The Keyboard is Org and works fine but the screen is from ebay. I bought the Macbook from someone on Facebook Market with a bad screen, He told me it was a 2018. So I ordered a 2018 screen installed it and that's probably where the problems started. I returned the 2018 screen and ordered the proper 2020 but I still didn't get backlight keyboard and camera. So I decided to pull the logic board and found L8570 blown and welded to the board. I got a copy of brdview and schematic from here I have a 10x binocular scope with a barlow lens, but I am not that great with electronics theory. I am a computer Tech and have been rolling with the punches through the years even dable with iPhone water damage. Luis Rossman, Paul Danials, Northbridge, Dos Dude and more have been mentors.. Hope you get my drift..