Re: ASUS ChromeBook C434T not powering on

For the record, the Chromebook I was trying to repair "magically" started to work again when I was trying to find which circuit was responsible for the almost short that I measured on the 3.3 V near ANX7447. I started by injecting 1 V/1 A from an external power supply, and the current consumption was very low, i.e. didn't seem like a short. When I upped it to 2 V/1 A from the external supply it suddenly jumped to 3.3 V, which I guess must've been coming from the battery, even though I suspect state of charge was low since it had...

Re: ASUS ChromeBook C434T not powering on



Not sure if you're still working on this, but it's a diode exactly the same to the one to the right (and in the same orientation). I would guess it's for protection and not vital to the function of the laptop. See photo, sorry for the bad quality since it's taken through the lens of the microscope ...

Re: ASUS ChromeBook C434T not powering on



Thanks a lot for the info, I'm trying to help a friend repair the same model laptop with seemingly the same issue. I'm also measuring low resistance to ground on what I believe is the 3.3 V. How did you find out that the short circuit was in ANX7447? Just pure trial and error or was it getting hot or something similar? I'm seeing 5 V / 0.12 A but nothing seems to heat up. 3.3 V and 12 V converters seem to be working but the 3.3 V at the consumers gets dragged down to a very low voltage due to the almost short circuit to ground...