Sound card not detected when closing cover lower casing
After installing a new ssd drive on my MacBook Air, everything seemed to work just fine (thanks to this site). Also performed a clean install of Sierre High.
While working, I did not put back ALL of the P5 screws back into place, holding the lower casing lid because I wasn't sure.
When finishing and putting back the last 4 screws, booting up ... no sound card detected.
Removed the lower casing cover and screws again, started up ... sound card working as normal.
Checked everything, closed again ... same problem, no sound card detected.
After some trying, removing and putting back a few screws, I found out it had to do with the four pressure contacts on the mainboard.
Did not find any info on these contacts and what they do exactly.
So when I leave my casing (partially) open, everything seems normal.
When I close the casing completely, no sound card detected, I guess when these contacts are pressed. Nothing seems to be damaged or squeezed anywhere.
Thanks - Paul