Macbook A1990 stuck on logo

[mr.Data]

Hello,

This Macbook Pro 2018 boots up and then gets stuck on the logo.
All the normal methods of resetting this Macbook have been tried but do not work.
I cannot get into recovery mode and there is no bar displaying, it's just the white logo on a black background.

Any help would be greatly appriciated.

[reformatt]

I first check the board under the microscope for any corrosion etc. Always like to rule out an obvious hardware issue first. As it's an A1990, the edges of the board near the fan intakes are obvious areas to check. Also check WIFI rails etc for shorts.

If that is ok, then I try to see if it comes up in either the Bootpicker or in Target disk mode (on Intel MAC's, use Option or T keys). I usually try to recover user data via Target Disk mode to another MAC (via a Thunderbolt 4 cable) before wiping the system with a DFU restore. Each time I've used this, the host MAC won't accept the users logon password to access the file system. If that is the case, it's usually corruption on the SSD.

Put in in DFU, and try a Revive, then Restore from your host MAC with Apple Configurator 2. Latter wipes the users data and you'll need their Apple ID/password in order to reactivate the MAC. Then you can reinstall MAC OS via recovery mode. You cannot install via USB on these things until the security level is dropped. But you can't do that until you reinstall via the Internet and setup an user account. Really is a long winded process.

https://logi.wiki/index.php/DFU_Mode_Restore_(Macs)

I also recommend an Apple Silicon MAC as the host for AC2 (I have an A2337 Air), and a Thunderbolt 3 or 4 cable. The MacVdmTool mentioned in the Wiki takes a lot of the guesswork when you are dealing with issues getting a MAC into DFU (like not knowing if the keyboard is any good for a start). This software only works on Apple silicon MAC's unfortunately.

[mon2]

Tested with SMC bypass?

Measure the voltage to ground of each pin on the battery connector. Testing for the state of the SMBUS lines that are used by the battery BMS. That is, some SMBUS / I2C line may be stuck and causing this frozen condition.

[mr.Data]

Can you show me which pins I need to measure?

When I disconnect the battery and close the lid and open it up again I get the startup link from Apple but I dont think that means anything right?