There’s a sizeable number of reports we’ve received so far about the #GalaxyJ7 not turning on or not charging so we hope this post today will be a helpful addition to our existing J7 troubleshooting material.
If you are looking for solutions to your own #Android issue, you can contact us by using the link provided at the bottom of this page.
When describing your issue, please be as detailed as possible so we can easily pinpoint a relevant solution. If you can, kindly include the exact error messages you are getting to give us an idea where to start. If you have already tried some troubleshooting steps before emailing us, make sure to mention them so we can skip them in our answers.
Below are specific topics we’re bringing for you today:
Problem 1: Galaxy J7 won’t charge, won’t turn on due to motherboard issue
Hello sir. I have bought a second hand J7 which said it has motherboard issue, but phone is not completely dead i am able to use the phone by using boot menu. The phone starts many of the time but often shut itself after showing Samsung J7 logo or after few seconds and then only way i am able to start my phone is by connection of charger. it takes several attempts but it gets started. After it’s started and somehow if it didn’t shut then the problem is it wont charge saying bad charger connected.
Also when my phone is off it won’t charge but keep blinking on white battery signal, and for that i have another J7 of broken screen to charge my battery so basically i have two batteries and both are working fine. I have also performed both hard and soft reset several time but that didn’t solve problem.
I have removed carbon from battery’s and also from phones pin of battery terminal. So my question is, will flashing with the stock ROM solve my problem? Or do i need to repair my motherboard and if so how much will it cost? Please reply as soon as possible. Thanks in advance. — Manu Yadav
Solution: Hi Manu. If you’re right in saying that the phone has motherboard issue, then flashing a different ROM won’t help at all. Any issue with the motherboard means a hardware problem and you can’t fix a broken component with a software solution like flashing. If you can manage it, then go ahead with motherboard replacement. We don’t know how much a motherboard for a Galaxy J7 will cost you though so you’ll want to contact retailers for that information.
Alternatively, you can try using the motherboard of your other J7 with a broken screen, as long as said motherboard is working fine of course.
Problem 2: Galaxy J7 overheating, won’t charge, won’t turn on
My phone is not responding. It turns off after showing the message like that you device heats up first prevent over heating and then charge it. Now it’s not responding when i connect it with laptop. Then the place under the camera gets heat up and the flash also triggers its SAMSUNG J7. Please resolve my problem. i have attempt all the solutions. — Meshu400
Solution: Hi Meshu400. If your phone is not responding at this time, you must make sure that you charge it long enough to ensure that there’s enough power in the battery. If you have another known working Samsung charger and charging cable, use it.
If the phone still fails to boot up even after connecting the charger for at least an hour, try to see if you can start the phone to alternate boot modes. Here’s how:
Boot in Recovery mode:
- Charge the phone for at least 30 minutes.
- Press and then hold the Home and Volume UP keys, then press and hold the Power key.
- When the Samsung Galaxy logo shows on the screen, release the Power key but continue holding the Home and Volume Up keys.
- When the Android logo shows, you may release both keys and leave the phone be for about 30 to 60 seconds.
- You can either wipe the cache partition or do a factory reset when in this mode.
Boot in Download Mode:
- Charge the phone for at least 30 minutes.
- Press and then hold the Home and Volume DOWN keys, then press and hold the Power key.
- When the Samsung Galaxy logo shows on the screen, release the Power key but continue holding the Home and Volume DOWN keys.
- Wait until the Download screen appears.
- If you can boot the phone in download mode but not in other modes, that means that your only way out may be to flash a stock or custom firmware.
- Use Google to look for a guide on how to do it.
Boot in safe mode:
- Charge the phone for at least 30 minutes.
- Press and hold the Power button.
- Once the Samsung Galaxy logo appears, release the Power key and immediately press and hold the Volume Down button.
- Continue holding the button until the phone finishes rebooting.
- Once you see the text “Safe mode” at the bottom left corner of the screen, release the Volume Down button.
- The only difference of safe mode from normal mode is that the former prevents third party apps from running. If you can boot the phone in safe mode but not in normal mode, uninstall all apps until the issue (that prevents you from booting normally) is eliminated.
All of these different boot modes require that you perform a certain combination of hardware buttons. If your phone remains dead or unresponsive, there must be a hardware malfunction causing it. You must let a professional check the device so the hardware can be examined.
As a good step before sending the phone in, try to see if it’s just a bad battery issue. If you have a friend with another J7, try to borrow his or her battery and see if it can make your phone to work. Otherwise, just skip buying a different battery and let a technician figure out the failure.
Problem 3: Galaxy J7 Prime not charging, not turning on
Hi. My Samsung J7 PRIME suddenly shuts off and unresponsive at all. I cannot turn it on. Tried charging it for over 10 minutes but still not working. The charging icon won’t even show up. WHAT SHOULD I DO? — Markryan79
Solution: Hi Markryan79. You may the same issue as Manu and Meshu400 above so please refer to our suggestions for them.
Problem 4: Galaxy J7 power menu randomly pops out
Phone will show the Samsung screen but stops short of fully powering up. It seems like the power button may be faulty because the only way to restart it is to pull the battery. However I question this hypothesis because I can get the logo screen to display.
Also when the phone has been running (a stroke of luck will get it to power on it seems), at random intervals the soft reset screen will pop up which also shows airplane mode. I’ve had to set the screen to dim after 15sec of inactivity because when the phone is on the power button has no effect on dimming the screen. I read through your articles and tried a few things but to no avail. Help? — Gabriel Blair
Solution: Hi Gabriel. One of the signs that a Power button is malfunctioning is when the power menu shows all of a sudden, as if you pressed the button manually. If you
get the power menu to come up randomly wherein the following are shown:
- Power off
- Data network mode
- Flight mode
then you should consider having the phone checked by a professional.
There are some websites that can give you step-by-step instructions on how to replace a component including a power button so you can visit them if you intend on replacing the button yourself. Keep in mind though that you still need the basic repair kit like the right screwdriver, heating equipment, and other tools to take your phone apart. You also need to buy the replacement component.
Problem 5: Galaxy J7 showing erratic battery levels, battery drains very fast
I just installed a new battery in my Galaxy J7. Immediately upon unplugging, power drops to 80%. When it gets down to about 40% it will all of a sudden drop to 0% and turn off. I cannot turn on again until it has charged for awhile. This is actually my second brand new battery. Any suggestions. — Paul.andersenpm
Solution: Hi Paul. Try to recalibrate the battery first. There’s a chance that Android may not be detecting the true battery levels at this time. If battery calibration won’t work though, it’s possible that there’s a motherboard malfunction involved. For example, if power management IC is broken, it can lead to incorrect battery readings all the time. Unfortunately, motherboard replacement is an unguaranteed, risky procedure. It’s also prohibitively expensive that getting a new replacement motherboard is not practical at all. However, if you don’t want to get a new phone at this time, the only option for you would be repair.
For reference, here are the steps on how to calibrate the battery:
- Use the phone by playing games or doing tasks to hasten power discharge, until the phone turns itself off.
- Charge the phone without turning it back on.
- Wait until the battery says it is fully charged to 100%.
- Wait for an hour before unplugging the phone from the charger.
- Use the phone until battery reaches 0% percent. The phone should turn off by itself.
- Recharge the phone to 100%, wait for an hour before unplugging it again.
- The battery should now be recalibrated. Observe how phone works.