Macbook A2337 Recovery

[Instafixx]

Device came in dead. Audio board has been tampered and the flex of the audio board is damaged as well.
Without these device turns on but shows exclamation and asks to restore. it will detect in AC2 in recovery mode but will not successfully restore.
Try forcing into DFU and did a restore and i encountered something weird.I get the battery charging sign even though battery isnt connected. only charger isnt connected.

With battery connected it goes half way on AC2 and device suddenly goes back to exclamation.

This is the error:
Unexpected device state 'Recovery' expected 'RestoreOS' (Probably caused by corruption or panic in the bundle's restored) [com.apple.MobileDevice.MobileRestore – 0xFAD (4013)]

 

[2informaticos]

"I get the battery charging sign even though battery isnt connected"
So macOS is loaded without battery connected?

 

[Instafixx]

During dfu restore without battery connrcted - AC2 went half way and on the mac after the apple logo i got the red battery logo with the bolt sign.
AC2 was stuck there.

 

[2informaticos]

Force the machine off pressing power button 5s first.
Then put in DFU using external switch method.

 

[Instafixx]

I am performing dfu restore without the audio board and power button.

you want me to replace them (as they are damaged) and then perform dfu?

 

[2informaticos]

You can use one more switch for PMU_ONOFF_L.

 

[Instafixx]

PMU_ONOFF_L to Ground right?

 

[Instafixx]

So i tuned it off using the external switch and entered dfu via the other switch. still got an error

RestoreOS device removed before restored completed [com.apple.MobileDevice.MobileRestore – 0xFAA (4010)]

 

[Instafixx]

Tried with board on bench.

RestoreOS device removed before restored completed [com.apple.MobileDevice.MobileRestore – 0x9 (9)]

Something weird i have noticed. When checking storage settings under iOS files i see "iOS 15.6.1 for Mac Studio" which corresponds to the file for Device Restore for this Macbook.
I have deleted the file and downloading again via AC2. Taking a bit longer than usual as well.
Is this normal?

 

[2informaticos]

Error 9 is related sometime with battery.

 

[Instafixx]

You want me to connect battery and then do dfu restore ?

 

[2informaticos]

Yeah.
Connect trackpad also.

 

[Instafixx]

RestoreOS device removed before restored completed [com.apple.MobileDevice.MobileRestore – 0xFAA (4010)]

with battery + trackpad connected

 

[Instafixx]

What should i do?

 

[2informaticos]

We don't have a clear description of all DFU error codes.
I saw threads on the forum where people got DFU completed after days of traying.
How can an error code help in such case?

You may have problems with CPU itself...

 

[Instafixx]

Was checking JE900. PP1v25_AWAKE_IO is 0.080 diode to ground.

I see this is directly linked to the CPU as well.
Should inject 1V?

 

[2informaticos]

Resistance is not low enough to heat anything; unless a thermal avalanche occurs.

 

[Instafixx]

Yeah. Nothing on the thermal cam.