Touch Screen Test
Drag your finger across every part of the grid. Cells light up as they register touch — any cell you can't paint marks a dead touch zone.
Works with fingers, styluses, trackpads and mice — on a non-touch screen it doubles as a quick cursor/digitizer check.
Tip: cover the edges and corners carefully. Edge zones fail most often, especially after a screen replacement.
Before you conclude anything
- 1. Remove any screen protector — bubbles and thick glass cause false dead zones.
- 2. Clean and dry the screen; moisture confuses capacitive touch.
- 3. Restart the device once — software can freeze touch regions too.
- 4. Repeatable dead zones in the same spot point to the digitizer hardware.
Touch problems are not pixel problems
The touch digitizer is a separate transparent layer bonded on top of (or into) the display panel. That's why a screen can look flawless and still ignore your finger in one stripe — and why a cracked digitizer can make a perfectly working display untouchable. If your issue is visual (dots, lines, glow), run the dead pixel check instead; if touches register in the wrong place or a zone never paints, the digitizer or its connector is the suspect.
Common patterns and what they mean
- A full-width horizontal or vertical stripe that never responds — classic digitizer row/column failure, common after drops and cheap screen replacements.
- Unresponsive edges — sometimes hardware, but also caused by ill-fitting cases and protectors, or by the OS's accidental-touch rejection.
- Intermittent dropouts everywhere — often software, a failing cable, or interference from a charger; test again unplugged after a restart.
Document a repeatable dead zone with a screen test report before a warranty or repair conversation.