A general guide to phone care and repair. For hardware damage, have your phone checked by a trusted technician.
A phone screen that suddenly displays green, white, red, or other colored lines does not always fail completely right away. However, this symptom requires attention because it is often related to the display panel, its connecting paths, or its control circuitry. Based on experience handling Android devices and iPhones, the way the lines appear can provide initial clues before a technical inspection is performed.
Identify the appearance of the lines and when they occur
Lines caused by panel damage usually extend vertically or horizontally and remain in the same position. On OLED screens, a green line can appear when a pixel path or part of the panel controller does not function properly. The line may remain visible from the startup logo and lock screen to the use of various applications.
Some lines appear only at certain brightness levels, when the device begins to heat up, or when the screen displays dark colors. If the line changes when the body is pressed or the phone is moved, there may be a problem with the panel or its connection. Do not deliberately press the screen to test it, as additional pressure may worsen the damage.
The most common causes
Impacts, drops, or pressure inside a bag can damage the panel layers even when the outer glass is not cracked. This type of internal damage often causes lines, dark spots, screen flickering, or unresponsive touch areas. Exposure to liquid and moisture can also affect the connectors or display circuitry, sometimes causing symptoms only after some time has passed.
Excessive device temperatures can make problems with the panel or display paths more noticeable. In addition, flex cable connections, connectors, or display control circuits can be affected by impact, corrosion, or age. In some cases, lines appear after an update or because of a problematic application, but lines that are consistently visible from the beginning of the startup process are more likely to indicate a hardware issue.
Safe checks you can perform
Start by restarting the phone normally. Once it turns on, check whether the line is already visible on the startup logo. Next, take a screenshot and view it on another device. If the line is not captured, the problem is likely related to the panel, display connection, or display circuitry. If the line appears in the screenshot, a system or image-processing issue may still be possible.
Make sure the operating system and applications are updated through the device's official menu. On Android, safe mode can be used to check for possible interference from third-party applications. Remove the case if the device feels hot, stop intensive use, and allow it to cool naturally in a dry, well-ventilated place. Back up photos, contacts, and important data immediately while the screen is still usable.
Do not press, massage, twist, or strike the screen. Also avoid applications that claim to repair permanent lines by flashing colors. These methods cannot restore damaged panel paths and may cause eye discomfort or prolong the screen's workload.
When to take the phone to a technician
A technician should inspect the phone if the line remains after the device is restarted, is visible from the startup logo, increases in number, is accompanied by flickering, causes the touch function to stop working, or appears with black spots. A device that has been dropped, subjected to pressure, or exposed to liquid should also be inspected promptly, even if it can still be used.
Turn off the phone and do not charge it if the screen is lifting, the body is swelling, the device generates unusual heat, or there is an unusual odor. These conditions may be related to the battery and require special handling. A technician needs to inspect the panel, connectors, flex cable, and display circuitry before determining whether the connection can be repaired or the display module needs to be replaced.
