SOLVED Keyboard and trackpad not working after motherboard replacement

[sunnysamossa]

Hi,

I have a MacBook Air 13" (Mid 2013). The motherboard died, so I replaced it with one I bought on AliExpress (same specs).

However, now neither the keyboard nor the trackpad works under macOS Big Sur. I replaced the keyboard cable, but the issue persists.

I’ve tried resetting the NVRAM and SMC, and I also attempted downgrading to macOS Catalina.

The strange thing is that both the keyboard and trackpad work fine when booting from a Clonezilla USB stick, and they also work in recovery mode.

I’m at a loss. Has anyone encountered this issue before? Is it a hardware or software problem? How can I fix it?

 

[Rodananne]

Just theorising here but if both keyboard and trackpad work in Recovery and under a different boot volume it sounds like a software issue. In particular the macOS itself.
You said you tried unsuccessfully to install macOS Catalina, why did that fail?

My best suggestion would be to boot the Mac from a different source, ideally using a bootable macOS installer or failing that an external drive with a working macOS on board. Download the installer for your OS of choice, use Disk Utility to erase the internal drive and the installer to install a fresh copy of macOS.

 

[sunnysamossa]

Just theorising here but if both keyboard and trackpad work in Recovery and under a different boot volume it sounds like a software issue. In particular the macOS itself.
You said you tried unsuccessfully to install macOS Catalina, why did that fail?

My best suggestion would be to boot the Mac from a different source, ideally using a bootable macOS installer or failing that an external drive with a working macOS on board. Download the installer for your OS of choice, use Disk Utility to erase the internal drive and the installer to install a fresh copy of macOS.

Hi! Thanks for your answer.!

Actually I succeeded in erasing the internal drive and installing Catalina. But the issue persisted. Then proceeded to erase the drive again and reinstalling Big Sur. Always the same issue. I'm beginning to think that it is a motherboard issue since it is the only thing that was replaced.

 

[Rodananne]

I think I'd agree on that.

 

[sunnysamossa]

Replaced the trackpad. Problem solved.