820-3209-A No track pad or keyboard

[Greg]

No signs of liquid damage, Have used a known good track pad. I know this model only uses USB not SPI so should be fixable . Should i check voltages on J5700 with track pad connected? Any known common issues here?

 

[2informaticos]

First check L5720 and R5730.
Also check R5704 and U5700 area.
If all OK, I recommend you to test known good TP flex.
Don't trust new chinese flex, try more...

 

[Greg]

All those are good area is very clean, Could it just be a bad U5700? have tested with known working TP and TP cable.

 

[2informaticos]

Is the last remaining to test, change it.

 

[Greg]

Replaced it with no change. It will do a SMC reset but not PRAM reset. Any other suggestions?

 

[2informaticos]

U5700 is not involved in SMC reset.

Check SMC_LID signal.
Did you try the MLB alone, disconnecting LIO flex?