820-3476 - Keyboard and trackpad not working

[Palhano]

Perfect board. No oxidation.

Does not work before starting MacOs. I changed the trackpad flex, it didn't work.

I checked the resistors near U4801, they are OK.

BUTTON_DISABLE - 0v
Smc_lid - 3.3v
PP3V3_S3_PSOC - 2.1v (weird)
USB_TPAD_N - 0.500 and 0v diode mode
USB_TPAD_P - diode mode 0.530 and 0v
TPAD_VBUS_EN - diode mode 0.730 and 2.2v

Some help?

 

[2informaticos]

Replace R4804...

 

[Palhano]

I replaced the R4804, it didn't solve the problem. but I discovered that pin 2 (PP3v3_S4) has 2.1v

 

[2informaticos]

Check U8000 area...

 

[Palhano]

problem was the U8000. Replaces and stabilized 3.3v_S4

Thank you very much for the help!