Symptoms
- Overall image looks dimmer than it used to
- Dark scenes are hard to see details in
- Picture looks fine in a bright room but dark at night
- Brightness changed after a software update
Likely causes
- CommonEco mode or ambient light sensor lowering brightnessMany TVs auto-dim to save energy or respond to room lighting, which can look like a fault.
- CommonBacklight or OLED brightness setting turned downThis setting is separate from 'brightness' and directly controls light output.
- CommonWrong picture mode selectedModes like 'movie' or 'cinema' are intentionally dimmer and warmer than 'vivid' or 'standard.'
- PossibleAging backlight LEDs (LED/LCD TVs)LED backlights dim gradually over years of use, especially on older sets.
What to do
- Turn off eco mode and any ambient light or energy-saving sensor in the picture settings.
- Raise the 'backlight' or 'OLED brightness' setting, which is different from the 'brightness' setting.
- Switch the picture mode to 'standard' or 'vivid' to compare against 'movie' or 'cinema' modes.
- Check if the dimness is worse on specific apps versus the TV's own menu, which points to an app-level issue instead.
- Reset picture settings to factory default and adjust from there if a recent change caused this.
- If the TV is 6+ years old and dim on every setting, aging backlight LEDs are the likely cause.
Tools and parts
LED backlight stripsSearch: “TV LED backlight strip kit for model”
When to call a pro
If brightness is maxed out in every setting and the picture is still dim, a technician can assess whether the backlight is worth replacing.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.