Baffling double brick - HP Chromebook 11 G9 EE

Support General Device Support
1

System Details

  • Device: DRAWLAT
  • OS: Linux
  • Firmware Type: UEFI Full ROM
  • Firmware Version: ?
  • Internal storage type: eMMC

I have two Chromebooks that refuse to turn on. When pressing the power button, nothing happens. When pressing power+Refresh, the power light turns on and then shuts off suddenly. The screen backlight turns on, very, very dim as well.

Steps to Reproduces

I had 1 Working Chromebook with Linux, full UEFI firmware installed. Worked great. I had another Chromebook which worked on ChromeOS. In process of disabling WP, it bricked as seen above. Tried reassembling in many ways, nothing fixed. Got CH341A programmer. Reflashed chip with full UEFI exactly to instructions. Nothing fixed. Maybe it’s a problem with the components? Tried swapping the motherboards inside the two chassis, and neither worked. Neither? Strange - maybe it’s a very broken Chromebook. Reassemble with original parts. Broken one is still broken, but now the originally working one is broken too. Try charging for a few hours, still nothing. Now I have two broken Chromebooks. Additionally, the originally working one sometimes when unplugged just flashes alternating on/off white.
Expected Behavior

Boots

I was quite careful with both boards but I don’t have the best workspace so it could be electrostatic? I tested battery voltage, is right. All cables are connected well. Screen cable is intact. Screws are in. Any advice on where to go?

2

I have ordered a SuzyQ cable to do some more debugging. Probably should’ve gotten one first…

3

this doesn’t sound like a firmware issue, given that it started before you did anything with the firmware

4

I think I found part of the problem - the lidstate and LID_OPEN in the EC are reported as closed. The lidstate in the AP is reported as open. Only manually enabling the lidopen in the EC can make it work, but it stops working after a reboot. Strangely, Linux CAN detect the lidstate, and auto shuts off the screen accordingly. ???

5

EN_BL_OD seems to be responding perfectly to the lid state. Could I redirect that somehow?

6

I would think fixing the EC lid detection would be a better option, something (magnet?) is causing it to report incorrectly