Boot fine in safe mode but touchbar and backlight keyboard doesn't work (I assume it's normal bc of safe mode). With normal boot the macbook ask me for a critical uptade, tried with wifi, wired cable and I also tried what this guy say on a forum (https://apple.stackexchange.com/ques...al-update-loop). No liquid damage, I had some weird stuff around U4200 (picture attached), the rest of the board is nice, I cleaned this area but still have the problem. I tried with a known good Touchbar, a know good casing and keyboard, also with disconnected display, still have the problem of critical update. I tried to boot on an external SSD (same), I also tried clear ME Region.
With all this done, I think it's a board level problem and I have make some measurements on J4401 and J4402.
J4401
PIN 10 DFR_DISP_INT = 0,05
PIN 12 DFR_DISP_RESET_L = 0
PIN 18 PP3v3_S0SW_DFR = 3,3V
J4402
PIN 20 PP1V8_S0SW_DFR = 1,8
PIN 19 DFR_TOUCH_ROM_WC = 0,04
PIN 18 DFR_TOUCH_RESET_L = 1,8
PIN 13 DFR_TOUCH_INT_L = 0,08
PIN 9 DFR_TOUCH_SPI_CLK_R = 0,08
U4406
PIN 4 DFR_DISP_SMC_RST_L = 3,42V
PIN 2 DFR_DISP_RSDT_L = 0V
PIN 6 PP1V8_S0 = 1,8V
R4400 = 98K OK
R4490 = 0,125MOhms NOK
So it's missing DFR_DISP_RESET_L and there is a strange value on R4490, it is a "no stuff" resistance and it should be 0ohms. Should I run a wire there ?
With all this done, I think it's a board level problem and I have make some measurements on J4401 and J4402.
J4401
PIN 10 DFR_DISP_INT = 0,05
PIN 12 DFR_DISP_RESET_L = 0
PIN 18 PP3v3_S0SW_DFR = 3,3V
J4402
PIN 20 PP1V8_S0SW_DFR = 1,8
PIN 19 DFR_TOUCH_ROM_WC = 0,04
PIN 18 DFR_TOUCH_RESET_L = 1,8
PIN 13 DFR_TOUCH_INT_L = 0,08
PIN 9 DFR_TOUCH_SPI_CLK_R = 0,08
U4406
PIN 4 DFR_DISP_SMC_RST_L = 3,42V
PIN 2 DFR_DISP_RSDT_L = 0V
PIN 6 PP1V8_S0 = 1,8V
R4400 = 98K OK
R4490 = 0,125MOhms NOK
So it's missing DFR_DISP_RESET_L and there is a strange value on R4490, it is a "no stuff" resistance and it should be 0ohms. Should I run a wire there ?