[SOLVED]820-2914 no keyboard/trackpad

[ajdoc]

Power button works fine.
Tested with 100% working trackpad/trackpad flex and keyboard.

Pin 30 PP3V3_S4 on J5713 got only 0.76V

Checked R5076 (got 100K) and on SMC_PME_S4_WAKE_L side got 1.03V and on PP3V3_S4 got 0.76V.

Replaced U5701 just in case but still same issue. USB mouse/keyboard works fine on all ports.

Any idea?

 

[dukefawks]

PP3V3_S4 got 0.76V. There's pretty much your answer. So check voltages at Q7800/02.

 

[ajdoc]

Thanks Duke.
Q7800/02 was 1.74V but then I saw a burned R7803 which on one side had 1.74V and on another was 3.3V.
Replaced R7803 and all works. Many thanks.

​​​​​​​Issue solved