A2442 - new logic board from Apple Self Repair now no backlight

[AKuchen87]

Hi there. I am currently trying to figure out if I am undergoing the sunk cost fallacy.

I've bought a very cheap MacBook Pro 14 A2442 off eBay. I did some checking and the symptoms were pointing towards a NAND failure.

After some consideration I got an original logic board from Apple as an replacement. However after installing I have no backlight.

I can see the Apple logo if I point a flashlight at it but the MacBook seems to be going to recovery mode.

anybody have an idea of what's up here? Is the board dead on arrival or is my screen defective? One thing that struck my eye was that instead of the 4 NANDs that should be installed there is a fifth sitting on one of the NAND sockets on the „left“. Very odd.

I am currently trying to figure out what my next step could be. Any advice appreciated.

Thanks!

[mon2]

Backlight will enable if the lid sensor is able to sense that the lid is open. Only then will the backlight enable. There is an assumption that the backlight cabling is properly seated. There is a lid sensor on these units that may need to be calibrated. Apple should have mentioned this.

Review these videos - they may help.

https://www.youtube.com/watch?v=u18D_NPGhzQ

https://www.youtube.com/watch?v=hrK5_Ar29-I

https://www.youtube.com/watch?v=j6yrl89fsQE

[AKuchen87]

Hi mon2! Thanks for the input. Apple only mentioned the TouchID which I replaced as well.

I've also thought that the LAS might be the issue so I disconnected it - under the assumption it behaves the same as on an MacBook Air and defaults to „open“. Should be like this shouldn't it? Backlight remains off.

backlight cabeling has been reset twice - so it should be ok.