Sound with a black screen is the most common TV fault there is, and the most commonly misread. Because the screen is dark, people assume the screen has died, and a screen is the most expensive part of any television. In most cases the screen is fine. What has failed is the light behind it, or one of the boards that drives the picture. You can narrow it down yourself in about a minute, before anyone visits.
What causes sound but no picture?
Sound proves the TV is powered and the mainboard is running, so the fault sits somewhere in the picture path. There are four places it can be, and they differ enormously in cost.
| Cause | How common | What you see | Repair cost level |
|---|---|---|---|
| Backlight failure | Most common | Faint image visible under a torch | Low to moderate |
| Backlight driver / power board section | Common | Faint image under torch, backlight never lights | Low |
| T-Con board | Less common | Nothing under torch; sometimes lines before failure | Low to moderate |
| Panel failure | Least common | Nothing under torch, often after an impact | High |
The torch test: a one-minute diagnosis
- Turn the TV on and play something with sound, ideally a bright scene or the home menu.
- Darken the room if you can.
- Hold a phone torch 5–10 cm from the screen, angled sharply, almost parallel to the glass.
- Look closely where the light hits. If you can faintly make out menus or moving images, the panel is alive and the backlight has failed.
- If you see nothing at all, try the TV’s own menu button: a menu that appears only under the torch still points to backlight.
A positive torch test is good news. It rules out the most expensive fault and points to one of the most affordable repairs.
What does the fix cost?
Delhi NCR market ranges for the two repairs that fix most sound-but-no-picture faults:
| Fault | 32" - 43" | 44" - 55" | 56" and above |
|---|---|---|---|
| Backlight / LED strip replacementSound works but the screen is black or unevenly lit | ₹3,000 - 8,000 | ₹5,500 - 12,000 | ₹8,500 - 18,000 |
| T-Con board repair or replacementHalf screen, double image, vertical lines | ₹1,500 - 4,000 | ₹2,500 - 6,500 | ₹4,000 - 12,000 |
Things to check before calling anyone
- Picture settings: an energy-saving or "screen off" mode can blank the picture on some smart TVs while audio continues.
- Input: switch to the TV’s own home screen. If that shows, the fault is the source device or HDMI cable, not the TV.
- Brightness and backlight settings in the picture menu, in case they were turned to zero.
- A full power cycle: unplug at the wall for 60 seconds, then restart.
Is it worth repairing?
If the torch test shows a picture, almost always yes. Backlight repair costs a fraction of a new set at any screen size, and the panel you keep is the most valuable part of the TV. If the torch shows nothing and the set has taken a knock, get the panel checked before assuming the worst, but also price a new TV before approving panel work.