This machine will boot to the login page fine. But once you login, the progress bar gets about 10% of the way across, stalls for around 1 minute or so, then the MAC reboots back to the login page. This machine had FileVault disk encryption enabled and appeared to be running Monterey.
Board looked clean, apart from a corroded cap near the WIFI IC (which was partially shorted). Fixed that but fault remained. It boots to recovery mode, you can run disk checks etc. But that also locks up after around 5 minutes. Pretty sure this was a bad touchbar, but didn't have one to hand. These are bloody expensive for this model...like 3 times the price of the older models!
Cut a long story short, I had a spare A2338 machine in for repair for other issues, so swapped the board into that chassis. Boots fine. But I've had bad touchbars before but they haven't prevented the MAC booting up, just issues with coming out of sleep.
The difference here was FileVault. I turned this off in the donor chassis, and when I reinstalled the board to the original chassis, it logged in fine, albeit with a dead touchbar. I'm assuming that this thing will have issues with coming out of sleep until I get the replacement touchbar. Machine was indeed running Monterey.
On an unencrypted device, the Touchbar should light up at the login page. However it does not do this at all on an encrypted device as MAC OS has not yet loaded. So it is hard to know that the touchbar is indeed faulty other than trying another or swapping it to another chassis. I don't know if this is an issue on later versions of MAC OS. I'm unclear as to why MAC OS boots fine with a dead touchbar, but crashes when you have FileVault turned on. It would seem to me that FileVault is completely superfluous now since the SSD on these is encrypted anyway by the controller. There is no point to it really.
Anyway, it's a strange enough issue to post it here.
Board looked clean, apart from a corroded cap near the WIFI IC (which was partially shorted). Fixed that but fault remained. It boots to recovery mode, you can run disk checks etc. But that also locks up after around 5 minutes. Pretty sure this was a bad touchbar, but didn't have one to hand. These are bloody expensive for this model...like 3 times the price of the older models!
Cut a long story short, I had a spare A2338 machine in for repair for other issues, so swapped the board into that chassis. Boots fine. But I've had bad touchbars before but they haven't prevented the MAC booting up, just issues with coming out of sleep.
The difference here was FileVault. I turned this off in the donor chassis, and when I reinstalled the board to the original chassis, it logged in fine, albeit with a dead touchbar. I'm assuming that this thing will have issues with coming out of sleep until I get the replacement touchbar. Machine was indeed running Monterey.
On an unencrypted device, the Touchbar should light up at the login page. However it does not do this at all on an encrypted device as MAC OS has not yet loaded. So it is hard to know that the touchbar is indeed faulty other than trying another or swapping it to another chassis. I don't know if this is an issue on later versions of MAC OS. I'm unclear as to why MAC OS boots fine with a dead touchbar, but crashes when you have FileVault turned on. It would seem to me that FileVault is completely superfluous now since the SSD on these is encrypted anyway by the controller. There is no point to it really.
Anyway, it's a strange enough issue to post it here.
