820-00165 NO KEYBOARD OR TRACKPAD

[2click]

Hi, this board is turning on, but when I get to the login screen, trackpad and mouse, just don´t work... But if I press ALT when the computer is starting, they both work, so it is not the keyboard nor the trackpad.

PP5V_S4_IPD = 5.1
PP3V3_S4_IPD = 3.3
SMC_LSOC_RST_L = 3.4
SMC_ONOFF_L = 3.4

never seen one like this...

 

[2informaticos]

Check R4850-53.
Post U4810 voltage, on the login screen.

 

[2click]

R4850-53 ARE OK
U4810
1 = 3.3
2 = 0
3 = 3.3
4 = 0
5 = 3.3
6 = 3.3
7 = 0
8 = 3.3

 

[2informaticos]

U4810 looks good.
Are you sure the 4 resistors all good?

SMC_LID steady high at J4800?

 

[2click]

All ohm values on R4850-53 are OK
SMC_LID = 3.42 steady

 

[2informaticos]

Then change trackpad flex/board.

 

[2click]

The trackpad and keyboard work fine, I used a different board to see if it worked, and it did just fine...

 

[2informaticos]

Then you have problems with trackpad connector, o a TPAD_SPI data line.

Just in case, check/replace R/Q4860.

 

[2click]

I replaced R4860 and Q4860 still the same... I checked all TPAD_SPI lines and all seems to be good, the resistors have their values... no open or broken resistor...

 

[2informaticos]

Then bad PCH.
As last chance, change trackpad connector.

 

[2click]

I don´t see why to change the connector, when I start the computer pressing ALT (Option) key, mouse and keyboard work fine, even the CAPS green light works, as soon as I leave the boot menu and the system starts loading I loose them both... worth reflowing the PCH ?

 

[2informaticos]

Before loading macOS drivers, trackpad works in USB mode.
After that, PCH enables SPI mode.
So should be PCH issue, or bad contacts on the SPI lines.