A2681 MacBook Air 13" Short on board question.

[Stephen]

The new generation of models appear to be more and more crapware designs that are throw aways...yet, the fans keep on purchasing them. Suspecting a flash fault but even that will be a no fix.

Flash Fault? oh no haha. From my understanding if something is going on with the hardware it would be noticed. I have come across faults like this with M1 MacBook Pro where if the Touch Bar is failed the revive process or restore process will fail unless you disconnect the Touch Bar.

[mon2]

Cross your body parts and let us hope for the best. Keep us posted on your progress. Still chasing the battery charger fault after the display has been replaced by 3rd party. Not yet convinced the fault has anything to do with the brand of the display. Almost had access to a lower cost model damaged A2681 unit that required a new display but it got sold before we could negotiate a deal.

[Stephen]

Top Case came in, new keyboard new trackpad, even swapped out the lid sensor and calibrated it with nerd tool. Computer will not revive. Keep getting errors. Looks like I am back to square one.

Battery Holds a charge, Keyboard goes into DFU, new daughter board, new lid sensor, new keyboard, new battery, new everything minus the board and LCD. I do not know where to go from here. It will not revive. I am assuming there is a communication error that is preventing this computer from functioning. I am about to scrap this computer and deem it a no repair no fix, even though the board turned on, and battery now holds a charge etc. I cannot get pass the (!) screen now.

[mon2]

IMO - The endgame here is to restore U1900 with the DFU method. Could you not reflash this target U1900 with a known good image or better yet, just swap it out with a known good flash? Just a suggestion.

The device is a fun sized part to work with. The dump of this SOC may be available on this website (BIOS sub-forum).

[Stephen]

hmm, I swapped it out and it was in DFU once I did that, tried flashing, and it got stuck. I am assuming that chip was faulty it came off a donor board. which more than likely had issues. So I guess the best way is to get that chip flashed, the old one.

[mon2]

The package used by Apple / Foxconn is the USON package. It is a rather tiny (at least for me and we work with down to 0201 parts for our PCB designs). Only in the last week, we now have proper tools & PCBs to R/W/E this same target device. From my last search, the supporting parts are only available on Aliexpress (China).

We ordered a few of these for experimenting:

https://www.aliexpress.com/item/1005...176218027WSdfL

[Stephen]

Dope I will order this

ORDERED

[mon2]

Suggest to order spares of the same flash devices that are onboard these units as well - they are just not available in North America unless you are interested to purchase a full tape & reel of the same and even then, there is a lead time.

We ordered the spares from here:

https://www.aliexpress.com/item/3305...21ef1802XEuJsa

Part # MX25U3235F

Cross check the part against the schematics and the body sizes. As noted, the adapters & the actual flash devices are rare to source in North America. Now we have 10-20 pcs in the building for more experiments.