A1707 critical update

[hgoncalves]

Hi,

I've an A1707 that is always asking for a critical update, even when installing a new macOS.

The disk is reconized in restore mode, it has Monterey instaled, and already run first aid with no errors.

Should I start with a DFU restore?

Don't know where to start.

Can you help?

 

[2informaticos]

DFU for A1707?

The update is required by touchbar.
Can't install it?

 

[hgoncalves]

Sorry, din't think it well about DFU...

The install always fail, and I'm stuck in this screen (loop)

 

[2informaticos]

Then check all about touchbar problems.
We have many threads and information on the forum.

 

[hgoncalves]

Hi,

Following Luke's post, I found that with the touchbar disconected, and in safe mode, I was able to install Big Sur, and now the mac boots in safe mode, and so, I supose that the problem is on the touchbar (not sure)

Shoul I replace U3900? Is there any way to phisical disable touchbar?

 

[2informaticos]

Any history available?

Did you check any signals and voltages on touchbaar connectors?

 

[hgoncalves]

Hi.

Client said that one morning this error appeared.

J4401 voltages:
PIN 3 = 0.450V
PIN 5 = 0.355V
PIN 9 = 0.402V
PIN 11 = 0.417V
PIN 15 = 1.8V
PIN 17 = 1.8V
PIN 21 = 1.8V
PIN 23 = 1.8V
PIN 4 = 0.330V
PIN 6 = 0.360V
PIN 10 = 0.062V
PIN 12 = 0V
PIN 18 = 3.3V
PIN 20 = 3.3V
PIN 22 = 3.3V

J4402 voltages (with J4401 cable conected):
PIN 1 = 0V
PIN 3 = 0.224V
PIN 7 = 0.324V
PIN 9 = 0V
PIN 13 = 1.790V
PIN 15 = 0V
PIN 19 = 0.520V
PIN 21 = 1.8V
PIN 2 = 0V
PIN 4 = 0.460V
PIN 8 = 1.8V
PIN 10 = 0V
PIN 14 = 1.8V
PIN 16 = 1.8V
PIN 18 = 1.8V
PIN 20 = 1.8V
PIN 22 = 5V

 

[2informaticos]

You must check with both cables connected.

I recommend you to test the machine with known good touchbar.