Samsung phone keeps turning off? 9 fixes that work

A Galaxy that shuts off on its own is frustrating, and it is easy to lose a call, a photo or a payment at the worst moment. The good news is that the pattern tells you a lot. A phone that dies at 20 or 30 percent has a different problem from one that dies when it is hot, and one that dies only in the camera has a different problem again. Start by working out which one yours is, then use the fixes below in order.

Match your symptom to the likely cause

• Dies with battery left (10 to 40 percent): a worn battery that cannot deliver power under load. The most common cause on phones that are two or more years old.
• Dies when you open the camera, play a game or use navigation: the same worn battery, or a hot phone protecting itself.
• Dies in the cold: cold lowers battery output for a while. Normal for a short time, a warning sign if it happens often.
• Dies while charging: a bad cable, charger or charging port, or the phone overheating.
• Turns off at about the same time each day: a scheduled power setting, an app or a routine in Modes and Routines.
• Turns off and then turns on again: that is a restart, not a shutdown. See the guide for a Samsung that keeps restarting.

Check the battery in Samsung Members

Samsung Members is already installed on most Galaxy phones. Open it, tap Support, then Phone diagnostics, then Battery status. It tests the battery and tells you whether it is normal or needs attention. Some models also show the battery’s usage count or health in Settings › Battery › Battery information. Menu names change between One UI versions and models, so if you cannot find a battery test, search Samsung Members for diagnostics.

A battery wears out because every charge cycle slightly reduces what it can hold and deliver. After a couple of years of daily charging, the percentage display can become unreliable. The phone may show 25 percent, but the battery cannot supply the burst of power the processor asks for, so the phone shuts off to protect itself. That is why replacing the battery fixes this problem more often than any software change.

Turn off auto restart and scheduled power settings

Some Galaxy phones have an Auto restart option that restarts the phone at a chosen time when it is idle, and older models have Scheduled power on and off settings. Go to Settings › Battery and device care › Auto optimization and look for Restart when needed or Auto restart at set times, then switch it off. Also open Modes and Routines and check that no routine is set to power the phone off or switch to a mode that does.

Check the SIM card and SD card

A faulty microSD card or a badly seated SIM can occasionally cause crashes that look like shutdowns. Power the phone off, remove the SIM tray, take out the SD card if you have one, put the SIM back and see if the problem stops. If it does, replace the SD card, because a failing one can also corrupt photos. Back up what you can before you test.

Why safe mode helps

In safe mode, the phone loads only the apps that came with it. If it stays on all day in safe mode but shuts off in normal mode, an app you installed is the cause. Restart the phone normally, then uninstall recently added apps one at a time, starting with anything that runs in the background, such as battery savers, cleaners and launchers. If the phone still shuts off in safe mode, the cause is the battery, the software or the hardware. See how safe mode works on Android for the steps on other brands.

Keep the phone from overheating

Phones shut off on purpose when they get too hot. Leaving one on a car dashboard, charging it under a pillow or gaming while it charges are the usual causes. Take the phone out of the case, move it to a cool, shaded spot and wait several minutes before turning it on. Do not put it in a fridge or freezer, because condensation can damage it. If it keeps getting hot while doing little, an app may be stuck in the background. Check Settings › Battery › Background usage limits.

Charging problems that look like shutdowns

If the phone turns off only when plugged in, try a different cable and a different wall adapter first. A damaged cable or a cheap charger can deliver unstable power. Look into the charging port with a flashlight, and if you see lint, gently remove it with a wooden toothpick with the phone off. If the problem continues, read the guide on a Samsung phone that is not charging.

What a factory reset will and will not fix

A factory reset fixes software problems, such as a corrupted system file or a bad setting you cannot find. It does nothing for a worn battery. Back up your photos, contacts and files first, because the reset erases everything. If the phone still shuts off right after a reset, with nothing installed, you can be sure the problem is hardware. See how to factory reset a Samsung for the steps.

Repair, replace or upgrade?

If the battery is the problem, a replacement from Samsung or an authorized repair center is usually the right fix for a phone that is otherwise in good shape. Ask for a quote first and make sure the shop uses a genuine battery. If the phone is several years old, no longer gets security updates, or the quote is close to the price of a newer phone, put that money toward an upgrade instead. Compare trade-in offers from Samsung, your carrier and resale sites, because they can offset some of the cost.

Check whether the phone is still under warranty or covered by a protection plan from your carrier or a third party. A defective battery within the warranty period is often replaced for free.

When it will not turn back on

If the phone shuts off and will not start, plug it in with a known good charger for at least 30 minutes, then hold the Power and Volume Down buttons for about 10 seconds. A fully drained battery sometimes needs time before the phone responds. If nothing happens after that, see what to do when a Samsung will not turn on.

Habits that help the battery last

• Avoid charging to 100 percent every night if your phone has the Protect battery option, which stops charging at 85 percent.
• Keep the phone out of direct sun and hot cars.
• Use the original charger or a certified one.
• Close heavy apps instead of letting them run in the background.