820-01700 no Touch Bar

[ajdoc]

Board was liquid damaged around J5100
Resistors around showing correct values.

Diode on J5100 show same values like another board.
No Touch Bar with brand new part.


SPI_DFR_MISO_R = 1.68V
DFR_TOUCH_INT_L = 1.73V
DFR_LID_OPEN_L = 0.02V
DFR_TOUCH_RESET_L = 0.058V
PP1V8_SLPS2RSW_DFR = 1.80V
PP5V_G3S_DFR_FILT = 5.13V

R5103 got correct 4.67k resistance.

SPI in diode mode:
SPI_DFR_MISO_R = 0.458V
SPI_DFR_CLK = 0.458V
SPI_DFR_CS_L = 0.448V
SPI_DFR_MOSI = 0.459V

Any idea?

 

[2informaticos]

DFR_TOUCH_RESET_L should be high, I think.
Can you compare with good board?

Check voltage and signals for J5110 too.

 

[ajdoc]

Dont have access to working board anymore.

J5110
DFR_DISP_VSYNC = 0.512V
DFR_DISP_INT 0.0V
DFR_DISP_TE 0.0V
DFR_DISP_RESET_L = 1.79V
PP1V8_SLPS2RSW_DFR = 1.80V
PP3V3_G3HSW_DFR = 3.34V

In Diode mode:
MIPI_DFR_CLK_CONN_FILT_P = 0.485V
MIPI_DFR_CLK_CONN_FILT_N = 0.485V
MIPI_DFR_DATA_CONN_FILT_P = 0.484V
MIPI_DFR_DATA_CONN_FILT_N = 0.484V
I2C_DFR_SCL_R = 0.445V
I2C_DFR_SDA_R = 0.445V

I compared J5110 in diode mode with another board where SSD failed and got the same readings.

 

[2informaticos]

Touchbar reset seems bad; can you compare with another machine (even other model)?

 

[ajdoc]

Made a stupid mistake - was checking voltage DFR_TOUCH_RESET_L and flex was not connected.
With flex connected got on R5103/1 1.78V and on R5103/2 1.77V

 

[2informaticos]

There must be something else affected by liquid spill.
Possibly bad traces, or even damaged T2 (its touchbar control section).