#1 HP x360 Chromebook 14A-CA, DA00GIMB6H0 , flooded, slow and stuck in tablet mode
Mobotool • 7 Травня 2025, 14:23
Dear colleagues,
I've entered the repair of the chromebook machines just one month ago and I've found some significant differences from the classic laptops or macbooks, so I'm searching some advices.
The owner of this chromebook gave it to me after it has been left flooded by water for almost a week, so chances of repair were not so high, the mainboard was oxidyzed in many spots but I made a nice cleaning, resoldering and component replaging work and now it is almost working.
Among other things I've cleaned many spots from oxyds, reballed CPU, EMMC, EC, replaced some corroded resistors/caps and one IC (MAX14637CV) connected to the main usb-c port.
Battery charges and keeps the charge and there are no heating spots.
The main problem right now is that it is very slow at startup process, I mean it needs around 30 seconds to showup the first chrome splashscreen and other 30 seconds to show the password request, but then if you access the user or the guest account, eveything goes smooth (instead a normally working chromebook takes 6 seconds to showup the splashscreen and 6/10 seconds to showup the pw request).
Another problem is that it doesn't completely shut down, I mean the screen goes black but the power light keeps on all the time...
Touchscreen is working normally.
Keyboard is working generally, it takes the button combos (esc+refresh+power, refresh+power) at startup but after loading ChromeOS other keys are not working (you can't enter the password by its internal keyboard, it works by touchscreen or usb keyboard), trackpad is indeed working.
I've compared this behaviour to a completely working HP 14B-CA chromebook, and I've observed that if the G-sensor (inside the display frame) is unconnected and you flip all the screen up to the tablet position, the keyboard and trackpad stop working (as they should), but then if you flip it back to laptop position , then the keyboard is not working anymore and the trackpad comes back to work (in order to make the keyboard work again, you have to shut the system and start it up again), that is the same behaviour that shows the machine I'm trying to repair.
It seems like the machine to repair is stuck into tablet mode and I can't put it in laptop mode anymore, like
there was a malfunction in the magnetic sensor (that I still haven't found on the board ).
That can explain why I can't power the device by only the power button on the side, it starts only by "refresh+power" or "esc+refresh+power" combos, like if the mainboard thinked that the lid is closed or in tablet mode and it doesn't allow the startup.
The mainboard ot the working chromebook 14B-CA (DA00G7MB6D0) is very similar to the one to repair and has the same connectors placing, I've put it in the other shell and with that one the system goes flawlessy, even keyboard, trackpad, screen orientation work good, so I think that G-sensor and magnets positioning are ok.
I haven't yet found a datasheet or boardview of this specific board so if you have one (o one from a similar board) it would be nice in order to find the actual positioning of the components.
I've found the datasheet of the ZBC/ZBD mainboard that has many similar ICs and architecture, but it's not so easy to compare the two ones even because there are no printings on the boards.
I triggered once a menù in which I could test the presence or add some new devices to the system (TPM, keyboard, wifi etc) , but this was before the ChormeOS was loaded, it was a combo like esc+refresh... I tried esc+maximize, esc+other keys but I can't access that menù anymore, do you know how to enter it?
Putting the device into recovery mode (esc+refresh+power) and pressing the tab key makes appear dos-like infos about the status of the system, but no errors are shown about keyboard, sensors, tpm etc
Please, can someone shad a light in some direction?
I've entered the repair of the chromebook machines just one month ago and I've found some significant differences from the classic laptops or macbooks, so I'm searching some advices.
The owner of this chromebook gave it to me after it has been left flooded by water for almost a week, so chances of repair were not so high, the mainboard was oxidyzed in many spots but I made a nice cleaning, resoldering and component replaging work and now it is almost working.
Among other things I've cleaned many spots from oxyds, reballed CPU, EMMC, EC, replaced some corroded resistors/caps and one IC (MAX14637CV) connected to the main usb-c port.
Battery charges and keeps the charge and there are no heating spots.
The main problem right now is that it is very slow at startup process, I mean it needs around 30 seconds to showup the first chrome splashscreen and other 30 seconds to show the password request, but then if you access the user or the guest account, eveything goes smooth (instead a normally working chromebook takes 6 seconds to showup the splashscreen and 6/10 seconds to showup the pw request).
Another problem is that it doesn't completely shut down, I mean the screen goes black but the power light keeps on all the time...
Touchscreen is working normally.
Keyboard is working generally, it takes the button combos (esc+refresh+power, refresh+power) at startup but after loading ChromeOS other keys are not working (you can't enter the password by its internal keyboard, it works by touchscreen or usb keyboard), trackpad is indeed working.
I've compared this behaviour to a completely working HP 14B-CA chromebook, and I've observed that if the G-sensor (inside the display frame) is unconnected and you flip all the screen up to the tablet position, the keyboard and trackpad stop working (as they should), but then if you flip it back to laptop position , then the keyboard is not working anymore and the trackpad comes back to work (in order to make the keyboard work again, you have to shut the system and start it up again), that is the same behaviour that shows the machine I'm trying to repair.
It seems like the machine to repair is stuck into tablet mode and I can't put it in laptop mode anymore, like
there was a malfunction in the magnetic sensor (that I still haven't found on the board ).
That can explain why I can't power the device by only the power button on the side, it starts only by "refresh+power" or "esc+refresh+power" combos, like if the mainboard thinked that the lid is closed or in tablet mode and it doesn't allow the startup.
The mainboard ot the working chromebook 14B-CA (DA00G7MB6D0) is very similar to the one to repair and has the same connectors placing, I've put it in the other shell and with that one the system goes flawlessy, even keyboard, trackpad, screen orientation work good, so I think that G-sensor and magnets positioning are ok.
I haven't yet found a datasheet or boardview of this specific board so if you have one (o one from a similar board) it would be nice in order to find the actual positioning of the components.
I've found the datasheet of the ZBC/ZBD mainboard that has many similar ICs and architecture, but it's not so easy to compare the two ones even because there are no printings on the boards.
I triggered once a menù in which I could test the presence or add some new devices to the system (TPM, keyboard, wifi etc) , but this was before the ChormeOS was loaded, it was a combo like esc+refresh... I tried esc+maximize, esc+other keys but I can't access that menù anymore, do you know how to enter it?
Putting the device into recovery mode (esc+refresh+power) and pressing the tab key makes appear dos-like infos about the status of the system, but no errors are shown about keyboard, sensors, tpm etc
Please, can someone shad a light in some direction?
