820-02020 A2338 Touchbar

Customer spilt pot noddle over keyboard. Mac would not power on. Cleaned out keyboard and removed logic board. Area around UT890, CT701 and LT700 corroded. The via under pin 1 of LT700 had completly gone so ran a wire from pin 2 PP5V_S2_DFR_FILT to CX401 Pin 1 ( I did not replace LT700)

After that repair the MacBook worked fine along with keyboard and trackpad, the only thing that did not work was the Touchbar.
Ultrasoniced that small area (not the whole board) and after that the MacBook still comes on and chimes but no backlight, keyboard or trackpad.

If I plug in a usb mouse and keyboard and click on a key or mouse button then the backlight will come on for about 3 seconds then go out again. Also if I breifly press the power button whilst the Mac is on the backlight again will come on for a couple of seconds and then go off again.

Any help appreciated.
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Staff member
Something happened in the ultrasonic process.
Probably some (already) corroded components dropped from MLB; or broken traces.