Macbook Air 2014 - No Backlight

[esbardu]

I've been given a Macbook air 13" 2014 with a damaged screen. Macbook is working fine with an external monitor and I realized than indeed the LCD is working but there's no backlight. Battery is flawless, same as SSD and overall performance is fine even having only 4Gb.
My friend told me that the Macbook was fixed once, non official support changed the lcd connector. I don't know if previous issue was the same, as the explanation given are not clear.

Now I don't know what to do, if I try a board swap maybe the issue is with the connector, if change the full LCD issue could be on the board. I have discarded replacing the connector as I don't have the time nor previous experience with Macbook airs.

Anyone has faced a similar siuation with a Macbook Air?

 

[diego.caraballo]

I've been given a Macbook air 13" 2014 with a damaged screen. Macbook is working fine with an external monitor and I realized than indeed the LCD is working but there's no backlight. Battery is flawless, same as SSD and overall performance is fine even having only 4Gb.
My friend told me that the Macbook was fixed once, non official support changed the lcd connector. I don't know if previous issue was the same, as the explanation given are not clear.

Now I don't know what to do, if I try a board swap maybe the issue is with the connector, if change the full LCD issue could be on the board. I have discarded replacing the connector as I don't have the time nor previous experience with Macbook airs.

Anyone has faced a similar siuation with a Macbook Air?

Hi there!
I asume that you already did an SMC reset, since screen brightness value is stored there and a corrupt value would cause no backlight at all.

If you are lucky, maybe is just the BL fuse damaged. There are lot of videos covering that, just one example:

If the fuse is OK, then you are probably dealing with a bad BL generator IC.
As the board had received a new LCD connector, it's fair to asume that the board got liquid damage at some point, since is the most common reason to replace that connector. If some of the liquid found its way under the IC, it could have corroded some PCB traces as well.
Either way is not an easy fix it unless you have the correct set of tools (station solder, microscope, etc).

Statistically speaking the most probably part at fault is the logic board. But again it's a 2014 model (not receiving any new macOS releases anymore) and is hard to recommend any investment unless you find a very good deal on a used
board (risking that you have a bad screen as well)

 

[esbardu]

Hi there!
I asume that you already did an SMC reset, since screen brightness value is stored there and a corrupt value would cause no backlight at all.

If you are lucky, maybe is just the BL fuse damaged. There are lot of videos covering that, just one example:

If the fuse is OK, then you are probably dealing with a bad BL generator IC.
As the board had received a new LCD connector, it's fair to asume that the board got liquid damage at some point, since is the most common reason to replace that connector. If some of the liquid found its way under the IC, it could have corroded some PCB traces as well.
Either way is not an easy fix it unless you have the correct set of tools (station solder, microscope, etc).

Statistically speaking the most probably part at fault is the logic board. But again it's a 2014 model (not receiving any new macOS releases anymore) and is hard to recommend any investment unless you find a very good deal on a used
board (risking that you have a bad screen as well)

Thanks a lot for your answer. SMC was reset. I am a developer, Mac fan but have no real soldering experience even though I would like to learn (probably once I am retired).
Considering your answer and my initial thoughts I will keep it as a test system and not spend a cent on it.