MacBook A1989. Stuck in DFU and won't turn on!

[PITERPENY]

MacBook A1989. does not work with dfu. Stuck in DFU and won't turn on!
20 volts and 0.00 amperes
Does anyone have any suggestions?
It's possible that the problem is in the EFI (BIOS),
who has the EFI ROM file please share

[PITERPENY]

????

[mon2]

Carefully measure the voltage to ground of ppbus_g3h at the fuse at the output of the isl chip.

[PITERPENY]

Carefully measure the voltage to ground of ppbus_g3h at the fuse at the output of the isl chip.

ppbus_g3h=12.31v

[PITERPENY]

does this board switch to 20 volts without a battery connected?

[mon2]

It may not - check Tim's YT videos (TCRS). I cannot recall which models of these craptops are requiring a battery to boot. He specifically noted this exact comment but not sure of which model. After you find out, continue to post the details here.

https://www.youtube.com/@TCRSCircuit

[PITERPENY]

It may not - check Tim's YT videos (TCRS). I cannot recall which models of these craptops are requiring a battery to boot. He specifically noted this exact comment but not sure of which model. After you find out, continue to post the details here.

https://www.youtube.com/@TCRSCircuit

I'll answer my own question above: should it be 20 when the board is removed, yes it should be!

[PITERPENY]

Well, I bought the same donor board and moved T2 to my board and the Mac was restored to DFU and the Mac started working! but the video on the built-in display is not displayed only on the external one! any ideas ?

[mon2]

Interesting. You have more courage than I on transplanting the T2.

Check the LID status. I believe there is a mux chip that steers the video signals to the lcd or external sink. Check the mux sel pin voltage.

[PITERPENY]

I rearrange T2 a lot (this is the same as CD3215), the main thing is to have lower heating so as not to disturb the RAM layer. and also losing an unlocked working T2 is a crime))). I'm not good at diagnosing, but I'm not bad at soldering chips! I can give you a masterclass)))

[PITERPENY]

LID_OPEN_RIGHT=1.796V
LID_OPEN_LEFT=1.796V
PP1V8_SLPS2R=1.8V
IPD_LID_OPEN=1.8V
SMC_LID_RIGHT=1.8V
SMC_LID_LEFT=1.8V

[PITERPENY]

EDP_INT_AUX_N = short circuit
you need to replace the processor (this is more difficult than replacing T2))

[mon2]

On your board, EDP_INT_AUX_N is shorted or just making a comment?

[PITERPENY]

EDP_INT_AUX_N in diode mode it should be 0.271(something like that) I have 0.000🥵

[mon2]

Ouch

macbook pro a1989 power on but black screen - Badcaps

[PITERPENY]

it won't stop me

[PITERPENY]

After rummaging in the box I found the same board without T2, after checking the CPU it was alive and I decided that I would transfer T2 and SSD from the board with a bad CPU. but that's not the case, the board on the dfu displays an error 4014 or 4042! hmmm(

[mon2]

Be sure there is not a thermal fault on the board.

https://youtube.com/shorts/ZfJK6OUMmt4?feature=shared

[bilel]

After rummaging in the box I found the same board without T2, after checking the CPU it was alive and I decided that I would transfer T2 and SSD from the board with a bad CPU. but that's not the case, the board on the dfu displays an error 4014 or 4042! hmmm(

T2 CHIP CAN'T RESTORE BY OTHER PC NEED INTERNET WIFI TO UPDATE

[PITERPENY]

T2 CHIP CAN'T RESTORE BY OTHER PC NEED INTERNET WIFI TO UPDATE

please be more detailed! help us inexperienced)