820-00165 some keys on keyboard not working.

[TBFix]

There is no sign of spillage but fan runs fast and some keys on keyboard dont work (Alt) there may be more keys but was trying to boot to external. I have replaced touchpad cable and tested with known good keyboard also.
I have tested J4800 in diode mode and all good. I have also tested all resistors on the smbus smc page 40 of schematic and all red good also.
I have tried reball smc and then replacing it but same issues.
Keyboard works in High Sierra external boot.
But alt key boot select doent work from outside os and fan runs high.
Any ideas appreciated.

 

[2informaticos]

"Keyboard works in High Sierra external boot."
Do you mean all the keys work correctly once logged into macOS.
Only have the keyboard problem before loading macOS?
If yes, there is a problem with USB mode; post U4810 voltages in this case.

BTW, SMC is not involved in KB/TP communication.

 

[TBFix]

Yes all keys work in OS . What controls keyboard? I couldnt see a keyboard controller chip.
U4810 voltages are
pin 1 = 3.3v
pin 2 = pulses around 2.5v
pin 3 = 0v
pin 5 = 3.3v
pin 6 = 0v
pin 7 = 3.3v pulsing
pin 8 = 3.3v.

Is (TPAD_USB_IF_EN_CONN) used in os and Spi used efi boot?

Also noticed it doesn't detect ssd.

Found PP3v3_s3 pulsing due to bad U8010 will try to swap that and see what happens.

Changed U8010 now sees keyboard and ssd. Installing OS currently.