MAcbook Air A1466 EMC 3178 - 2017 Boot

[Sergio Kub]

Could someone help me?
I have a Macbook Air A1466 EMC 3178 - 2017, board 820-00165 and sometimes the boot interrupts with an image of a folder and a question mark.
Could it be the BIOS?

[mon2]

I would try to clean the contacts of the removable SSD with IPA (alcohol) and then test again.

[Sergio Kub]

mon2
I've already cleaned it with IPA and heated each contact terminal in the SSD slot, and I've also replaced the NVME SSD. Every now and then, the paste and the question mark appear. Strange, I've never had a problem like that. Thanks.

[Sergio Kub]

I removed the board and noticed that it had solder flux marks on the top.
They had already handled it and hadn't been careful.
I returned it. Thank you!