You plug in your phone and, instead of charging, it shows a water-drop icon and a message such as "Moisture has been detected" or "Unplug charger". The phone has stopped charging on purpose. Electricity and water in a USB-C port corrode the contacts quickly, so the phone refuses power until the port is dry.
Do this first
- Unplug the cable from the phone straight away.
- Hold the phone with the port facing down and tap it gently against your palm a few times to shake out loose water.
- Wipe around the port with a dry, lint-free cloth. Do not push the cloth inside.
- Leave it somewhere with moving air, port facing down or sideways. In front of a fan is ideal.
- Wait. A few drops clear in 30 minutes to an hour. A proper soaking can take several hours.
What not to do
- Do not blow into the port. Your breath is humid and pushes water further in.
- Do not use a hair dryer or heater. Heat damages the seals and the battery.
- Do not insert cotton buds, tissue or toothpicks. They leave fibres and can bend the centre tongue of the port.
- Do not keep plugging the cable in to check. Each attempt puts current through wet contacts.
Need power right now?
If your phone supports wireless charging, use it. The charging coil is sealed inside the back of the phone and does not use the port, so it is safe as long as the back of the phone is dry.
If the warning stays after the port is dry
Sometimes the alert persists for hours on a phone that is clearly dry, or appears when the phone has not been near water. Work through these:
- Check the cable. The moisture may be in the cable's plug, not the phone. Try a different, dry cable and charger.
- Look inside the port with a torch. Lint or corrosion on the contacts can trigger the sensor. Green or white crust means corrosion and needs a technician.
- Restart the phone with nothing plugged in.
- Clear the USB service cache (Samsung). Open Settings, then Apps, tap the filter icon and turn on "Show system apps", find USBSettings, open Storage and tap Clear cache. Then restart.
- Consider the weather. In very humid conditions, or after moving from an air-conditioned room to hot outdoor air, condensation alone can set it off. Let the phone reach room temperature.
Can sound help?
Only a little. On most phones the main speaker sits right beside the charging port, so the vibration from a water eject tone can help shake droplets loose from the area. It cannot dry the port itself. Use it for the speaker, and rely on air and time for the port.
When it is a repair job
If the warning is still there after a full day of drying, with a different cable, the port's sensor or contacts are probably corroded. A service centre can clean or replace the port. On many phones it is a separate small board and not an expensive part.
iPhone users see a similar alert. That one is covered in iPhone charging port liquid detected.