"#9. Galaxy S3 displays grey battery icon
Q: Hi, hope you are well and can help me out. I'm having issues with my S3. I did an update to the new 4.3 when I was promoted to by the device, everything worked well and was having no issues for about 2 - 3 weeks. However I was in my room when my cell slipped off the bed and landed on the carpet (not hard surface) and started to reboot, It continuously restarted so I left it on and it drained the battery, I then plugged it in to charge and see if it had stopped its crazy ways as I plug it in the grey empty battery screen comes up and then restarts this continues over and over.
I have opened the device checked the checked all connections I have also checked the power on off button this seems to be triggering correctly, I haven't been able to access the home button but this should not restart the phone if it is held down, only turn the screen on or off. Is there some device failure Maybe dead battery. I also tried disconnecting individual devices at a time to see if one was broken, camera, speaker, and this did not change the outcome. Regards, Steven.
A: The grey battery icon that comes out whenever you connect the charger means that the phone doesn't recognize it as the "original" charger and two of the most common reasons are the microUSB port is corroded with dirt, and one of the pins is bent that proper contact is impossible.
That said, inspect the port on the phone to see if there's corrosion or if a pin is bent. For corrosion, a small and dry brush can help clean out the port. For the other issue, a toothpick could bend back the pin to its original location but be very careful when you do so, you might end up bending it beyond repair or breaking it.
If the port has already been cleaned and pins looked straight and in place, inspect both ends of the cable you're using. The same things could happen. However, if all your efforts fail, bring the phone to a technician and have it repaired."

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