Sony xperia xz3 H9436 only works in safe mode and flight.

[Matthew Dean1]

I bought a used phone that had been dropped so the backside was cracked. It restarts after some minutes in normal mode. It works in safe mode and flight mode. I have tried a factory reset in the menu but it is the same. I have Android 10.

 

[B. Diddy]

So it doesn't detect the SIM card? Are you certain that model supports the network bands that your carrier uses?

Considering that it was damaged, I wouldn't be surprised if the cell antenna or radio was damaged as well.

 

[mustang7757]

You have lot of 3rd party apps?
Possible one of them causing this since works in safe Mode.
Try resetting network?

 

[Matthew Dean1]

I do not have any sim card at the momemt. I only use wifi a 4g. Not any apps. Its the same even after a factory reset. Only restarts in normal mode. The average memory and temp is on cpu 40 and 62% after a boost with the app Memory Booster. Battery is on 34. Flight mode seems to work fine.

 

[B. Diddy]

Unless you're using an eSIM (which I don't think that phone uses), you have to have an active SIM card from your carrier to make regular phone calls or access mobile data. There's no way to access 4G mobile data with wi-fi only.

 

[mustang7757]

I do not have any sim card at the momemt. I only use wifi a 4g. Not any apps. Its the same even after a factory reset. Only restarts in normal mode. The average memory and temp is on cpu 40 and 62% after a boost with the app Memory Booster. Battery is on 34. Flight mode seems to work fine.

So only wi-fi?

 

[Matthew Dean1]

Yes i can access wifi with my huwaii router. Even in flight mode.

 

[B. Diddy]

It's normal to be able to turn on wi-fi in Airplane Mode. You can also turn on Bluetooth in Airplane Mode. The main function of Airplane Mode is to turn off the cell radio.

 

[Matthew Dean1]

I get noticed cpu temperatur is 60 or 70 for some seconds and then around 41to 46. If something was boken should it work in airplane mode then to? I only have 5 apps besides standard.

 

[B. Diddy]

What are you using to record the temperature? It would seem unusual for the temp to jump up 20 degrees, and then back down again in just a few seconds, so I would wonder if there's something faulty with the temp sensor.

What broken component are you wondering about that should still work in Airplane Mode?

 

[Matthew Dean1]

I use Memory Booster. I can't understand why it works fine in plane mode and not in normal

 

[Matthew Dean1]

I guess i need a special cable if i want to try a reset by computer? I have a x86 computer and read i need x64? And 200gb of free space. I only have a usb cable suited to Sony Xperia XA and similiar phones. This must have a larger micro contact. I at the momemt use my charger to my Asus Chromebook. It has the same volt 5v and 3a. It supported 3 different voltages to so i hope the batteri don't takes damage.

 

[B. Diddy]

Don't use "memory booster" apps. They cause more problems than they claim to solve. Let the Android system manage RAM on its own.

Just to be clear, when you say it works fine in Airplane Mode, do you mean it doesn't randomly reboot? But when you turn off Airplane Mode, it does randomly reboot?

You shouldn't need to connect to a computer to do a factory reset. Since you already tried a factory reset, and the problem still happens, it's almost certainly a hardware problem. I'm not sure it's worth continued efforts to try to fix.

 

[Matthew Dean1]

Yes after some minutes in normal mode. I thought the Android copy on the phone might be damaged so a new computer installation would work better. Is it another motherboard funcfion for plane mode? Like it was 2 different cards running the phone.

 

[Matthew Dean1]

I tried to stream live video in 720p and to record with Du recorder. It worked fine in 1h and with a cpu temp of 45 and battery on 34. I guess it cannot be a cpu problem.

 

[B. Diddy]

I'm not a technician, but I'm guessing that when the phone tries to access the cell radio, something goes wrong, like a short, or maybe the chip is quickly overheating.

Airplane Mode isn't a motherboard function -- it's a software feature that turns off the cell radio.

Another word of advice: avoid anything from DU. They're well-known to be shady. https://forums.androidcentral.com/ask-question/976116-du-recorder-safe.html

 

[Matthew Dean1]

Can i turn off the cell radio in otherway then plane mode?

 

[B. Diddy]

Not that I'm aware of. I'm not quite understanding the issue here -- if you don't use a SIM card, and the device malfunctions when the cell radio is on, then why not just keep it in Airplane Mode and use it as a wi-fi only device?

 

[Matthew Dean1]

Yes it works to. Read it could be solved by turning off the sensors to. But i guess it is not the best. I guess all sensors is off then.

 

[Matthew Dean1]

I tried a sim and it found the sim and restarted to configurate but it is the same restarts in normal mode.