Since yesterday, my Fairphone 3+ (I upgraded it myself) randomly blacks out/switches off on a 2 hour basis. I can only switch it on again if I remove the battery first, and then put it back.
It shows no sign of life during/after the crashes. I get no feedback like vibrations if I press the power button, so I assume it is not the display.
The battery itself seems to be fine, same level of energy after the crash, the measured voltage seems to be fine.
How can I debug it?
Ps: I did not change/update the software for at least 3 months, so I would exclude software issues.
The few options i would check are
a) ensure i don’t have an SD card formatted as internal
b) try starting in safe mode and see how that is after a few hours
c) dismantle the phone more completely
d) contact official support
e) contact a #fairphoneangel
f) do a factory reset
As others mentioned. Bad connections can cause issues. Disassemble, clean every connection (Deoxit spray or similar), reconnect and see if this helps. If not then you most likely have a faulty mainboard (RAM faults cause random crashes).
I would not use Deoxit. It is more for heavier electrical work and is likely to be too corrosive for a phone.
Read up on it. The company do make one for gold contacts but still I wouldn’t use it.
Usually it is a spray that can get it’s way into the modules - not beneficial at all.
If you see problems with contacts clean them individualy with an ear bud soaked in min of 60% alcohol. Well overproof pure spirit or isopropyl alcohol which can be 90% to 96% .