Why does iPhone4 unlock when it is cold?

Reason: iPhone4 uses a capacitive screen. One of the main disadvantages of capacitive screen is drift. When the environmental temperature and humidity change or the environmental electric field changes, the capacitive screen will drift and cause inaccuracy.

1. Forced shutdown: Press and hold the power (power key/on/off key) +Home key at the same time, and release the Home key after a black screen appears. A white apple logo will appear within a few seconds after you release the Home button. Don't release the power button at this time. After the white Apple Logo disappears and the screen closes, complete the shutdown.

2. Forced restart: Press and hold the iPhone's power and Home button for a few seconds at the same time, and then release the white apple on the phone screen. After that, the iPhone automatically restarts.

3. Sometimes, if the iPhone encounters particularly cold weather or dry fingers, the so-called "touch screen failure" will occur. Please use it in a suitable temperature environment, and the fingers touching the screen should not be too wet or too dry.

4. It is also possible that the iPhone has fallen before, and the screen may be broken. Please go to the Apple Retail Store for help from after-sales staff.