Samsung Galaxy S3 was quickly adopted by the users because of its great features and performance. Even though many people never experienced any issues with this device, others did complain about some bugs and glitches. Some owners of the device reported a problem saying that Samsung Galaxy S3 is stuck on download mode and whatever they do, they cannot connect to Odin3. One user said that his Galaxy S3 was working fine, but suddenly the phone turned off and restarted by itself. After the phone turned on, a black screen appeared with the android symbol that said ‘downloading, do not turn off.’ This means, your Samsung Galaxy S3 is Soft Bricked.
Here come the solution for Samsung Galaxy stuck in download mode.This is the common issue reported by Samsung Galaxy users.They are saying that the phone was running normally but suddenly it turned of by itself and then turn on again but this time a black screen appears with the Android logo and a message saying “Downloading, do not turn off. Boot Into Download Mode On Galaxy S6 & S6 Edge Long press on the power key to turn your device off. Turn it back on by pressing and holding the Volume Up, Home, and Power keys.
Some of the occurrences of Galaxy S3 Soft bricks are:
When you are able to enter the Download mode then you have a device which is powering on at least halfway. This means your device is soft bricked and it can be repaired.
If you are not able to enter download mode or recovery mode or if your phone cannot boot up at all, it means your Samsung Galaxy is hard bricked, and chances of repairing it by yourself are very low.
Seealso: EffectiveTipsonHowtoSpeedUpSlowRunningAndroidPhone
Normally, Samsung Galaxy S3 is stuck on the download mode screen occurs because of a bad update, corrupted firmware or a custom ROM flashing gone wrong. To exit from this download mode, just pull the battery out from your phone, wait for few seconds and insert it back. After inserting the battery and turning on the phone, connect it to your PC and once it is booted fully, check whether you have the right driver installed on your computer. If the phone connects and comes up as a storage device, then your phone has been fixed and your problem is solved.
However, if the phone does not do anything, then you must download Kies. Samsung Kies contains the drivers that are required for the phone to communicate with the PC.
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Sometimes upgradingyourSamsung Galaxy S3 tothelatestfirmwarecansolvetheproblem.Therefore,readthispost:How toupdateSamsungGalaxy S3 toAndroid4.4KitKat
IfyouareplanningtoaflashstockROM,doalittleresearchonHowtoflashstockRomViaOdin.
Herearefewstepsthatyouneedtodotoget4.2.2onyourSamsungGalaxyS3.
3. Once you are done with the backup, Getrootaccess.(OPTIONAL)
4. NextDownloadCustomFirmware
5. DownloadOdin.
6. ExtracttheFirmwareZipFile
7. OpenOdin.exe
8. Now you are required to takeyourphoneintoDownloadmode.Disconnectyourphonefromthecomputer.PressandholdVolumeDown + Power + Home button altogether.
9. Pressvolumeupbuttonthecontinue
10. ConnectyourGalaxy S3 tothecomputer,onOdin,youwillseeanaddedmessage.
11.Clickonthe(AP,OR,PDAforthelaterversion)buttonandclickbrowsefortheFirmwarefileyoujustdownloaded (VeryImportant – MakesureRe-Partitionboxisnotchecked).
12.Finally,yourPhonewillbeflashed,withaStatusPassatthetopleft. But in case youseefail, thendisconnectyourphone,pulloutthebatteryandrepeatthisstepagain.
Once you complete flashing the stock ROM, your phone will restart automatically and you will be on the home screen again. Flashing a ROM will delete all data from your device so you will have to restore all the data stored on your device once you have established that your Samsung Galaxy S3 is working as expected.