How to fix Galaxy S7 that loses battery faster after installing an update, won’t charge to 100%

Today’s #GalaxyS7 troubleshooting article wants to tackle three related power issues that were seemed to be triggered by updates. We’ve been receiving reports that many S7 owners started having problems after installing system updates on their phones. Some of these issues are specific to losing battery percentage faster after the update. If you’re one of the unlucky S7 owners to have experienced this type of issue, make sure to read through the entire article.

Problem #1: Galaxy S7 stopped charging in car after an update

I have a Samsung S7. Using the original USB charging cord, I have always been able to charge in the car while phone is on. It’s not speedy but it at least maintains the current charge +/- 2%. Just this week, when I plug into the car, it keeps beeping like the charge is initiating, the lightning bolt shows, but the beeping is persistent as though the chargability keeps getting lost, and I lost 10% in the course of an hour. I unplugged from the car and plugged into my PC when I arrived at my destination, and no issue, charge went immediately. I recently did the system update. Not sure if I need to contact Samsung or how easy/quickly I can get a resolution, or if you can help out. — Aml1128 [email protected]

Solution: Hi Aml1128. Charging bugs can sometimes occur due to factors unique to a certain device. These factors can vary a lot. We don’t want to discuss the factors but the possible solutions that you can try when faced with charging issues like the one you’re contacting us about.

Force restart

Some charging bugs develop after the device has been running for some time. In order to ensure that you minimize these types of bugs, make sure that you restart your phone regularly. At other times, restarting a device not only prevents bugs from developing but actually fixes them. Should you come across another charging glitch like the one you describe above, make sure to force reboot your S7. Here’s how:

  1. Press and hold the volume down button and don’t release it.
  2. Then, press and hold the power key while holding down the volume button.
  3. Keep both keys held down for 10 seconds or more.

Recalibrate Android and battery

Another good way to prevent encountering power-related or charging issues is by calibrating the operating system and battery regularly. Over time, Android may no longer be able to get accurate battery levels. This situation can lead to charging or power problems so make sure that you recalibrate once every few months. If you can do it once every month, that’s even better. To calibrate Android, follow these steps:

  1. Drain the battery completely. This means using your device until it powers down by its own and the battery level reads 0%.
  2. Charge the phone until it reaches 100%. Be sure to use original charging equipment for your device and let it charge up completely. Do not unplug your device for at least two more hours and also don’t use it while charging.
  3. After the elapsed time, unplug your device.
  4. Restart your S7.
  5. Use your phone until it completely runs out of power again.
  6. Repeat steps 1-5.

Clear the cache partition

If you’re positive that the issue started right after a factory reset, then you should consider wiping the cache partition. This is an effective solution for a lot post-update issues and yours is not an exception. Android will rebuild the system cache after some time so you don’t have to worry about losing the cache. To wipe the cache partition:

  1. Turn off your Samsung Galaxy S7.
  2. Press and then hold the Home and Volume UP keys, then press and hold the Power key.
  3. When the Samsung Galaxy S7 shows on the screen, release the Power key but continue holding the Home and Volume Up keys.
  4. When the Android logo shows, you may release both keys and leave the phone be for about 30 to 60 seconds.
  5. Using the Volume Down key, navigate through the options and highlight ‘wipe cache partition.’
  6. Once highlighted, you may press the Power key to select it.
  7. Now highlight the option ‘Yes’ using the Volume Down key and press the Power button to select it.
  8. Wait until your phone is finished doing the Master Reset. Once completed, highlight ‘Reboot system now’ and press the Power key.
  9. The phone will now reboot longer than usual.

Problem #2: Galaxy S7 overheating, drains battery fast after an update

Hi after denying the new software update several times it automatically installed itself. Since then my phone has slowed down, freezes up for short periods, drains the battery very quickly, and overheats. And it all started to a lesser extent with the update prior to this one. Now with the newest update my phone will only work for for 5 mins with my gear vr headset before it overheats. — Geoff Gaffield [email protected]

Solution: Hi Geoff. Newer firmware builds can usually lead to performance issues for older devices as they require more capable hardware to run. We don’t know what exact software update you installed but if it’s Android Oreo, it may potentially cause some slow downs for the Galaxy S7. Android Oreo is optimized for the S8 and S9 devices so older S7 may find it a little more resource demanding given the inferiority of your device’s hardware compared to the newer ones mentioned. Overheating is not expected to occur though so there must be other factors causing the symptoms you mention. To see if these factors are software in nature, do a factory reset and see how your S7 works afterwards, when there are no apps installed. To factory reset your S7:

  1. Create a backup of your personal data.
  2. Turn off your Samsung Galaxy S7.
  3. Press and then hold the Home and Volume UP keys, then press and hold the Power key.
  4. When the Samsung Galaxy S7 shows on the screen, release the Power key but continue holding the Home and Volume Up keys.
  5. When the Android logo shows, you may release both keys and leave the phone be for about 30 to 60 seconds.
  6. Using the Volume Down key, navigate through the options and highlight ‘wipe data / factory reset.’
  7. Once highlighted, you may press the Power key to select it.
  8. Now highlight the option ‘Yes — delete all user data’ using the Volume Down key and press the Power button to select it.
  9. Wait until your phone is finished doing the Master Reset. Once completed, highlight ‘Reboot system now’ and press the Power key.
  10. The phone will now reboot longer than usual.

Problem #3: Galaxy S7 won’t charge to 100% after installing system update

Hi. I have a Galaxy S7. It was doing fine till I installed a system update. Now it will not charge to 100% and it dies before it gets to 0% . It charges to different levels, but the battery usually shows 82%. The lowest I’ve seen the battery go is 20%, it died shortly after. I tried turning on the phone in safe mode and a factory reset. It does charge more when the screen is open, as I’m typing this it has charged to 87%, which it never does when the screen is off. It is working fine otherwise. I know it is ‘older’ but it is actually new to me, it was a hand me down gift, but I really like it, and it was fine till that system update! — Rachel

Solution: Hi Rachel. One of the drawbacks of using “older” smartphones is the fact that they usually come with older batteries as well. And in today’s smartphone-saturated world, having an older battery is a disadvantage. Older Lithium-based batteries like the one in your S7 means that it may not be able to give good performance day in and day out. In some cases, older Lithium batteries can also lead to charging issues or cause the device to randomly restart on its own.

The description of your problem appears to be consistent with having a bad battery, which means that your S7 may now be using a depleted battery. To see if you can fix the issue, consider doing the following:

  • wipe the cache partition
  • recalibrate Android and battery
  • factory reset

If you’ve already did these steps prior to contacting us, then you have no other choice but to contact Samsung so they can replace the battery for you.


TheDroidGuy Mailbag

🛠️If you have questions, check our Help section for details on how to submit your questions.💡


Posts You Might Like

Leave a Comment