Dead, or just behaving as though it is
Four quite different faults look identical from the outside. The phone may have no charge at all and a charging path that is not working. It may be powering on and failing to start Android, which looks like nothing if the screen is also dark. It may have a battery that can no longer deliver current under load, so it dies the moment anything demands power. Or the screen may have failed while the phone is running perfectly well. Working through them in order costs nothing and avoids the expensive assumption.
Match the symptom first
| What you see | Most likely | Where to start |
|---|---|---|
| Nothing at all, not even a charging light | No charge, or the charging path | Different cable, charger and socket |
| A vibration or a light, but no picture | It is running; the screen or the boot | Force restart, then look in a dark room |
| The manufacturer logo, over and over | Android is failing to start | Safe mode, then recovery |
| It boots then dies under any load | The battery cannot hold up | Age of the battery, and swelling |
| It restarts randomly through the day | Software, heat or battery | Safe mode for a day |
| Hot to the touch and will not start | Stop | Unplug it and let it cool before anything else |
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The checks, in order
- Charge it properly for thirty minutes before judging anything A deeply discharged battery shows no sign of life for several minutes, and sometimes longer. Use a charger and cable you have seen work today, in a socket you have tested, and leave it alone.
- Change the cable, then the charger, then the socket One at a time. A cable that charges another phone is not proof; some cables carry power at a rate this phone rejects. This step alone resolves a large share of dead phones.
- Clean the charging port Pocket lint compacts into the port and stops the plug seating fully. With the phone off, a wooden toothpick and a bright light, gently. Never anything metal.
- Force a restart Hold power and volume down together for twenty to thirty seconds. The exact combination varies by manufacturer, but this one covers most phones, and it restarts a device that is powered but stuck.
- Look at the screen in a dark room With the phone silent, cover it and look closely. A very faint image means the phone is running and the backlight has failed, which is a screen repair rather than a dead phone.
- Try safe mode if it does start Restart and hold the volume down key while it boots, or hold the power-off option until it offers safe mode. If the phone is stable there, the fault is an installed app, not the hardware.
- Use recovery to clear the cache partition, not to reset Power and volume up, on most phones, from a powered-off state. Clearing the cache partition is harmless. A factory reset from here erases everything, so do not select it while your data is still on the phone.
- Stop before the factory reset if the data matters A repair shop can often recover data from a phone that will not boot. A factory reset guarantees they cannot.
Once it is running again
A phone that restarts by itself under load, or dies at twenty per cent and then shows forty per cent when plugged in, is usually telling you the battery is finished. That is an ordinary consumable, typically after three to five years of daily charging, and replacing it is much cheaper than replacing the phone.
If safe mode was stable and normal use is not, the culprit is an app. Uninstall whatever was added in the days before it started, in reverse order, and check the battery usage screen for anything running constantly that should not be.
AccuBattery. Estimates the real capacity of the battery against its design capacity by measuring actual charge cycles. The clearest evidence for whether a replacement is the answer.
Battery Guru. The same job with more detail on charging behaviour, temperature and what is draining the phone between charges.
Device Info. Battery health, temperature, charging current and the exact hardware in the phone, which is what a repair shop will ask you for.
Device Info HW. Small, plain and detailed, including the sensor and component identifiers that tell you which screen or battery part a given model takes.
Phone Check and Test. Walks through every component in turn: screen, touch, speakers, microphone, sensors and charging. The right tool after a repair or before buying a used phone.
Test Your Android. An open alternative for the same hardware checks, with no advertising to work around.
Phone Doctor Plus. A guided set of about thirty tests with a simple pass or fail, which is easier to hand to somebody else than a screen of numbers.
CPU-Z. Confirms the exact chipset, memory and battery details, useful when a listing or a repair quote does not match what is actually in the phone.
Find Hub. Worth checking before a phone goes to a shop, so you know whether it can still be located and, if it comes to it, erased remotely.
Google Photos. The reason to set up backup properly once the phone is working again. The next time this happens, the photographs will not be the part that hurts.
When it is worth paying somebody
- Different cable, charger and socket
- Cleaning the charging port
- A force restart
- Safe mode and uninstalling a suspect app
- Clearing the cache partition
- A swollen or hot battery
- Liquid damage of any kind
- A charging port that is loose in the frame
- Data you need off a phone that will not boot
- Anything that needs the phone opened
Two things are worth knowing before you hand it over. A repair shop can often read the storage from a phone whose screen or board has partly failed, but full-disk encryption means they will need your unlock code, and no shop can get past that without it. And if the phone is still under warranty, opening it yourself usually ends that, so make the call about the warranty before the toolkit comes out.
Charge it properly on a known-good cable, force a restart, then try safe mode. Stop at the factory reset if the data matters, and stop entirely if the battery has swollen.
Frequently asked questions
How long should I leave a completely flat phone charging before giving up?
At least thirty minutes on a charger you know works, ideally an hour. A deeply discharged battery charges very slowly at first and shows nothing on the screen while it does.
What is the force restart combination?
Power and volume down held together for twenty to thirty seconds covers most phones. A few use power and volume up, and some older models have a pinhole. The manufacturer's support page is the reliable answer for a specific model.
Will clearing the cache partition delete my photographs?
No. Clearing the cache partition in recovery removes temporary system files only. The factory reset option in the same menu does erase everything, which is why it is worth reading the screen carefully.
The screen is black but it rings when I call it. Is it dead?
No, that is a phone running normally with a failed screen or backlight. The data is intact, and a screen replacement recovers both the phone and everything on it.
Is it worth replacing the battery on an old phone?
Usually, if the phone still gets security updates and the rest of it works. It is a fraction of the cost of a replacement phone and is often the only thing wrong with it.
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