820-01055 Keyboard and Trackpad
MacBook Air Retina 13" 2020 - 820-01055
The MacBook Air Retina 13" 2020 with board number 820-01055 has the T2 Chip. I've made a new discovery about serialisation.
A 820-01055 came to me water damaged, no sign of life.
I opened the board and saw that the trackpad got pretty wet.
A lot of corrosion on the connector, the flex cable was burned and some chips on the trackpad looked ugly.
The MacBook works as long as I unplug the trackpad/keyboard flex.
I changed the trackpad for a new one, I bought a new flex cable, the MacBook works but... I can't : Press Q (A for Qwerty keyboard), D, all the Function keys.
So I bought a new keyboard... took everything out of the case and changed it with the new one => Same problem.
Asking on the Discord someone gave me a clue : There is a T2 chip on this model so there must be some serialisation....
So I took off the ST32F103B6 chip from the original trackpad - WARNING : it's an underfilled chip be careful. I took off the same chip from the new trackpad and put the Original ST32F103B6 on the New trackpad - WARNING : Protect everything around this chip with kapton tape and be careful. Then I got a working MacBook Air with working keyboard and trackpad. One last thing I wanted to try is the daughter board 820-02005-A. This board get the connection for keyboard, keyboard backlight, and trackpad link. This board also has two chips for keystrokes and some others related to keyboard. When I put a new daughter board on this MacBook, I lost the FN keys...
MacBook Air 13" 2020 (820-01055) have some T2 serialisation on keyboard and trackpad :
You can change just the keyboard without issues.
You can't just change the trackpad, nor the daughter board.
If you need to change the trackpad, you need to have with you the original ST32F103B6 chip that came from the original trackpad.
If you need to change the daughter board, you need to have with you the 4BRT chip that came from the original daughter board.
For the moment I don't know if there is a way to dump some chips in order to reprogram them more easily because swapping ST32F103B6 is dangerous.