Today I received a Samsung Tab 6 which does not power on. The tablet belonged to the customer’s sister who unfortunately passed away.
The tablet looks to be in excellent physical condition and is still under warranty. Samsung is aware of the data recovery efforts that will be performed on this device and will honour the warranty of the device because they have been able to assess the device before we take it apart.
The tablet appears to be completely non responsive. It does not turn on or request power from the charge port’s data lines.
Standard hard reset procedures do not cure the issue so dis-assembly will be the next step.
The Tab 6 and a lot of other tablet devices these days are a sealed unit with glue under the edges of the screen. Special care must be taken to ensure the device isn’t damaged further as the display is very fragile behind the front glass layer.
I need to slowly and carefully apply hot air and lift the edges of the display with a thin razor to cut the adhesive. After 10 minutes of careful work, the display is completely free and I am able to see the internals of the tablet.
The tablet is in amazing condition internally as well. No dust, no damage, no liquids. This is most likely a firmware or ESD shock issue. The memory chip is UFS and is definitely encrypted so repairing the tablet is our best option.
Firstly I check the tablet’s voltage rails with and without the charger connected and it would appear the Battery Management System is not responding. This means the tablet will not be able to turn on, turn off, or charge.
Next I check the battery voltage. Battery voltage is 3.2V and this is usually the voltage of a flat lithium-ion battery. Since the battery is flat and the BMS isn’t responding, I have to charge the battery carefully myself.
I use the intelligent power supply to supply 2 amps of 4.2v limited power to the battery for half an hour to charge it up to about 20%.
Connecting the battery back to the tablet and attempting power and hard reset procedures does not change anything. I check the BMS again and it is in a different state to before but it still refuses to ask the charge port to supply power or let the tablet turn on.
I short the 2 Power_Good lines coming from the BMS to trick the device into powering up normally even when it thinks something is critically wrong. The device starts normally and asks for the pin that I have been provided. The tablet is unlocked and the data is intact and accessible.
The Type C port on the bottom of the device is still not negotiating any power states or data links so we must get the data off some other way. It is a good thing that most Samsung devices still have an SD card slot because I can use the built in system backup utility to backup all the data.
Once the data is copied to the SD card, I verify it is accessible and re-assemble the device. I won’t restore the adhesive because the tablet is approved for replacement and still needs repairs to get the charge port working.
The customer is very happy with the data we have saved for them and I am happy that this was a pretty straight forward case.
