Hello. I got a 820-00840 that was liquid damaged and both usb ports would give me 0v when connecting a charger. Had to replace both CD3215 chips and some caps and resistors around them to restore 20v and the board boots. Everything was working fine including the power button, so I sold the laptop to someone. 3 weeks later, it was returned to me because they could not get it to turn on. When I tested it, it would only turn on when you connect a charger to it. It does not automatically turn on when you open the lid or when you press the power button. Also, when the computer is on, I cannot turn it off using the power button at all. I have to do SMC reset to get it to turn off. I tested the board alone with just a charger connected and tried to trigger SMC_ONOFF_L, and PM_PWRBTN_L stays at 3.3v and the board does not turn off. I also tried to trigger PM_PWRBTN_L and SMC_ONOFF_L also stays at 3.3v and the board does not turn off. I am thinking there is an issue with the SMC but wanted to confirm first before changing it.