Hello everyone,
I'm new to the forum,sorry english is not my first language too, i got a basic plus knowledge, but now i am in this situation where i need some help , i spend good few days reading forums , here and outside , to help my problem solve, with no luck
long story short, i bought macbook pro a1989 820-00850, clean no water damage which was stuck on 5v 0.200/300a i read a lot of forums what that could be , it indicated to faulty corrupted t2 rom
of course before jumping to conclusion and connected to DFU , i believe i done basic checks
ppbus_g3h f7000 pin 2 12.32v
then i checked all 4 pp3v3_upc_tb_ldo no short no beepbeep
diode red prob to ground
c3208 0.521
cb408 0.515
cb308 0.520
cb3108 0.521
then i find info i need to Measure the standby voltage of the T2 chip, which is supplied by the U7800
L7660 PP3V3_G3H 3.3V
L7806 PPVDDCPU_AWAKE 0.75
L7810 PPVDDCPUSRAM_AWAKE 0.8V
L7811 PP0V082_SLPDDR 0.82V
L7813 PP1V8_SLPS2R 1.8V
L7814 PP1V1_SLPS2R 1.1V
L7817 PP0V9_SLPDDR 0.9V
F7000 PPBUS_G3H 12.31 ALL OF THEM IS GOOD AND SAME
IN THE SAME MANUAL IT SHOWS THEY REMOVE T2 ROM RE FLASHES IT AND CONNECT TO APPLE CONFIGURATER 2 AND DO DFU MODE AND MACBOOK START WORKING AGAIN.
I DONT HAVE THAT PROGRAMER I CAN MAKE IT MY WAY BUT WHEN I WAS READING IN BADCAPS , ITS VERY HARD TO GET THIS BIOS , BUT SOMEONE OFFER TO WRITE A2179 BIN FILE, SO I THOUGHT TO MY SELF A1989/A1990/A2179/A1932 HAVE SAME ROM CHIP , AND I HAD IN MY SPARE PILE A1932 THIS A4770 ROM CHIP, I DE-SOLDER AND PUT ON MINE A1989
and then from 5v 0.200/300a it change to 5v 0.041/0.050a
I CONNECTED TO APPLE CONFIGURATER 2 , MACBOOK BEEN FIND STRAIGHT AWAY, I START DOING DFU RESTORE , BUT I GOT A MESSAGE
THE OS cannot be restored on this device
Gave up waiting for device to transition from DFU state to DFU state,
com.apple.MobileDevice.MobileRestore -0xFCA (4042) i am omg ðŸ˜ðŸ˜ðŸ˜ðŸ˜ðŸ˜ðŸ˜ okey let start looking for more info then i find its something with ssd could be a problem
i find people talking about to check pp0v9_ssd0 i find out a c9022 tested 0v no short ,diode red prob to ground 0.400v looks okey to me ,
then i red a1989 repair wiki about dfu
T2 firmware will be stuck at 5v 0.060 amps and typically will have PPBUS present and PP3v3_S5 missing. PP5V_S5 will often be present.
but i dont have PP5V_S5_LDO 0V
AND THE LAST TO add when i connect macbook charger in my termal camera i can see not very hot but hot to see on a termal camera t2 chip is heating up u3900
i would really appreciate if someone can guide me true because at this moment , i dont know where to move next .
I'm new to the forum,sorry english is not my first language too, i got a basic plus knowledge, but now i am in this situation where i need some help , i spend good few days reading forums , here and outside , to help my problem solve, with no luck
long story short, i bought macbook pro a1989 820-00850, clean no water damage which was stuck on 5v 0.200/300a i read a lot of forums what that could be , it indicated to faulty corrupted t2 rom
of course before jumping to conclusion and connected to DFU , i believe i done basic checks
ppbus_g3h f7000 pin 2 12.32v
then i checked all 4 pp3v3_upc_tb_ldo no short no beepbeep
diode red prob to ground
c3208 0.521
cb408 0.515
cb308 0.520
cb3108 0.521
then i find info i need to Measure the standby voltage of the T2 chip, which is supplied by the U7800
L7660 PP3V3_G3H 3.3V
L7806 PPVDDCPU_AWAKE 0.75
L7810 PPVDDCPUSRAM_AWAKE 0.8V
L7811 PP0V082_SLPDDR 0.82V
L7813 PP1V8_SLPS2R 1.8V
L7814 PP1V1_SLPS2R 1.1V
L7817 PP0V9_SLPDDR 0.9V
F7000 PPBUS_G3H 12.31 ALL OF THEM IS GOOD AND SAME
IN THE SAME MANUAL IT SHOWS THEY REMOVE T2 ROM RE FLASHES IT AND CONNECT TO APPLE CONFIGURATER 2 AND DO DFU MODE AND MACBOOK START WORKING AGAIN.
I DONT HAVE THAT PROGRAMER I CAN MAKE IT MY WAY BUT WHEN I WAS READING IN BADCAPS , ITS VERY HARD TO GET THIS BIOS , BUT SOMEONE OFFER TO WRITE A2179 BIN FILE, SO I THOUGHT TO MY SELF A1989/A1990/A2179/A1932 HAVE SAME ROM CHIP , AND I HAD IN MY SPARE PILE A1932 THIS A4770 ROM CHIP, I DE-SOLDER AND PUT ON MINE A1989
and then from 5v 0.200/300a it change to 5v 0.041/0.050a
I CONNECTED TO APPLE CONFIGURATER 2 , MACBOOK BEEN FIND STRAIGHT AWAY, I START DOING DFU RESTORE , BUT I GOT A MESSAGE
THE OS cannot be restored on this device
Gave up waiting for device to transition from DFU state to DFU state,
com.apple.MobileDevice.MobileRestore -0xFCA (4042) i am omg ðŸ˜ðŸ˜ðŸ˜ðŸ˜ðŸ˜ðŸ˜ okey let start looking for more info then i find its something with ssd could be a problem
i find people talking about to check pp0v9_ssd0 i find out a c9022 tested 0v no short ,diode red prob to ground 0.400v looks okey to me ,
then i red a1989 repair wiki about dfu
T2 firmware will be stuck at 5v 0.060 amps and typically will have PPBUS present and PP3v3_S5 missing. PP5V_S5 will often be present.
but i dont have PP5V_S5_LDO 0V
AND THE LAST TO add when i connect macbook charger in my termal camera i can see not very hot but hot to see on a termal camera t2 chip is heating up u3900
i would really appreciate if someone can guide me true because at this moment , i dont know where to move next .
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