A2141 Screen replacement. Boots screen freezes on Apple Logo 1/3 status bar unless connected to second monitor.

[abajor]

Having this very weird issue.
The owner of this laptop complained about screen being intermittent when opening and closing, and has been using the laptop on a thunderbolt video connection since the screen failed.

I swapped with a working screen from an A2141 waiting for parts.

The Os exhibits this weird behavior where it boots to to 1/3 the status bar, then it makes the boop sound. It's at the log in but for whatever reason the desktop isn't loaded.

The laptop boots fine into recovery mode. I updated from Monterey to Sonoma and the laptop still has the same issue. It also appears to happen with an External Big Sur boot.

The one thing I have figured out is if I cold boot with my Saitechi USB dongle with HDMI out I get video with the external screen set to primary, and the laptop screen set to secondary.

I can't find any options to alter this behavior. Does anybody have any idea what might be happening here? Is there a fix, or did apple start doing some funny T2 serial matches with screens on the 16" model?

[mon2]

This model had flexgate issues as well.

Have the owner reached out to Apple? They need to fix what they build.

https://www.ifixit.com/Answers/View/...comes+and+goes

[reformatt]

My immediate thought is a malfunctioning lid angle sensor, as A2141 does have this 'feature'. If you are having flex cable issues, this is also worth checking out for liquid damage.

I don't swap out screens on MAC's with flex cable problems, I refer them straight to Apple. The design is so flawed, that if the owner creates this problem, they will create it again and it is guaranteed to come back demanding warranty. The opening at the back of the MAC allows dust/grit/sand in quite easily damaging those flexes. Had an A2337 in the other day with it, and you could still see the sand around the bezel. Does it say in the T&C's anywhere about taking a MAC to the beach could destroy your display assembly?

Utterly shit design and Apple need to be called out for it.

[abajor]

Damn Ok. I will probably have to do that.
I did try changing the angle sensor. I know that's a huge issue with swapping the M series screens, aside from the Serial Matching.

[mon2]

Review this thread on the calibration tool and a DIY project:

A2442 hinge sensor has liqud damage - Badcaps

[reformatt]

Damn Ok. I will probably have to do that.
I did try changing the angle sensor. I know that's a huge issue with swapping the M series screens, aside from the Serial Matching.

Watch this to see if your problems line up maybe?

https://www.youtube.com/watch?v=fOzO...=LouisRossmann

He states that the problem initially happened after he swapped the display assembly, and affected the calibration of the angle sensor. I do like his comment that we may soon have to use GSX to flush the water after we take a shit.

[abajor]

Doesn't seem like Apple is acknowledging this problem, at least the representative I'm on the line with says he can't find any active or inactive programs to replace defective screens with flexi connectors, their site only mentions keyboard (butterfly key) and battery warranty replacements.
Although I do find articles claiming apple will repair it for free if you send it in.

[abajor]

It really is a baffling problem though.
As far as I can tell the angle sensor is working correctly since I moved it with the screen.

It boots into the safe mode terminal fine.
It boots into recovery modes fine.

If I attach a USB-C to HDMI hub the screen comes up fine on both monitors.

If I close the lid the HDMI connected monitor becomes the primary (So the angle sensor is working).

If I just boot the machine it doesn't matter what OS, Big Sur, Monterey and Sonoma all freeze on the Apple logo. I can enter the password and watch the touch bar change.

If I start the machine with the USB-C to HDMI hub and remove it The laptop screen freezes on that last image.
It will not wake up either screen if I insert the USB hub after booting.

This is absolutely the weirdest problem. I don't know if there is some esoteric hardware configuration in the SMI? I've tried resetting both PRAM and SMI multiple times.

[mon2]

Go up the ladder with Apple. Reference the articles you have found. See if there are law firms suiting up to sue this company. Contact them with your case details. They must be held responsible for the crap they are building. They cannot have the mega profits from poor designs and still prevent proper servicing of the hardware. Personally, toss and turn in my sleep if we find even a hint of a concern on our many product designs. We constantly study ways to build a better product. They must do the same.

Can you DFU this unit? Does the touch bar work properly? If not, definitely attempt a DFU.

[reformatt]

Doesn't seem like Apple is acknowledging this problem, at least the representative I'm on the line with says he can't find any active or inactive programs to replace defective screens with flexi connectors, their site only mentions keyboard (butterfly key) and battery warranty replacements.
Although I do find articles claiming apple will repair it for free if you send it in.

This is par for the course. They only ever react if there is enough media coverage or there is a class action lawsuit. They haven't acknowledged any issues with this design other than the 2016 Macbook Pro's. If any displays have been replaced for this issue outside of that program, it has been as a courtesy and nothing else.

Attached are some photos of a screen I replaced off an A2337 recently. You can see quite clearly the defects in the flex cable caused by grit getting in that opening. I usually see it with kids school machines, or people who are just outright filthy. The flex cables can be replaced if you are a complete masochist. In this case I used an aftermarket display, but told the customer that any damage to these cables is their responsibility.

Have you tried Safe boot per chance when booting into MAC OS? Also confirm Touchbar and Trackpad are working correctly (they both have lid open signal going to them). Seen some weird stuff when either of those aren't working properly.

[abajor]

One other lead I have on this situation from another repair tech, sometimes when a screen fails it damages the circuit that transitions from integrated CPU graphics to the secondary graphics chip. I suspect this is what's happening.
I would assume that Safe Mode and Recovery mode both preferentially use integrated graphics or generic graphics drivers.

I had a similar boot behavior trying to install upgraded OSX with open Core on a Mac Pro, with a RX580 GPU. The screen would freeze on the apple logo with about 1/3 status bar.

[reformatt]

Yes I've seen that display MUX fail when there is liquid damage on the LCD connector (in that case you get 60V from the backlight into the one of the data lines). Usually results in no image at all though. In the models with no mux, this destroys that data line in the CPU.....

I do also recall a thread a while back on an A1398 where the display would disappear on login. The solution was to force the output to the dGPU rather than the integrated CPU graphics so have a look at this page

https://support.apple.com/en-au/1022...%20preferences.

If you have a spare working chassis, then I swap the motherboard into it as a sanity check. Had an A1706 which would crash after it went to sleep and woke up. Had no idea, but swapping the board into a spare chassis proved it wasn't the board. Turned out to be the Touchbar in the end.

[abajor]

As a last ditch effort, I changed the motherboard to screen connector and now it just works. It also appears someone else has been in this machine before all the ribbons have been lifted.

Very weird symptoms though. Are there alternate signal paths on the connector?

I suppose I should try his old screen now just to make sure.

[abajor]

The most interesting thing about the LVDS cable. When I unscrewed it, the screws on the retention bracket seemed under torqued and I didn't need to unsnap the lvds from the board it just fell out as soon as I unscrewed it.

The owners says they got the laptop new from his IT department back when it was ostensibly new and nobody had ever been into the laptop.

One of the first things I noticed was the tell tale signs of gouges on one of the speakers from some sloppy tech using a plastic pry tool. I always just use a sucker if I can't just lift it far enough with my finger nails.
And of course all of the ribbon cable pulls were lifted.

The customers original screen works fine. Ironically I was originally going to try the LVDS first but my partner told me ITS NEVER THE LVDS ON THE BOARD if there's no liquid damage.