LCD Backlight Problems

Typically we see a lot of sets with some sort of backlight problem - this is mostly because people and manufacturers like to run the sets with the backlight at 100%. Unfortunately with LED backlit sets this causes LEDs to fail, often just outside of the warranty period. Below we list the common faults and list the best ways to fix them.

Dark/Black Spots On Screen

If you have some dark or black spots on your LCD screen, then it's typically a sign that one or more of the LEDs on the backlight strips has gone bad. In the case of edge lit LCDs you will see that an entire line on your screen appears to be darker than the rest.

In order to repair this, you will first need to buy a replacement set of strips - we recommend searching your model number on https://www.shopjimmy.com to find the correct part number and to be able to purchase the strips. We would recommend that you buy a full set and swap them all out at the same time, the repair process is quite time consuming and the cost of buying one strip vs a whole set is fairly minimal.

If you can not find the replacement strips you need on https://www.shopjimmy.com or are based outside the USA, we would recommend https://www.aliexpress.com/ as another great place to be able to find new and reconditioned LED strips.

Once you have the strips, then you will need to take the entire set apart and carefully remove the fragile LCD screen from the set.

If you wish to swap out the LED Strips, continue reading to the bottom of the page to find out how.

If you are proficient with desoldering and re-soldering of surface-mounted electronic components / have a hot air rework station then you can buy the individual leds and swap out just the damaged ones on the strip, although we would not recommend this due to the amount of effort and the possibility of the replacement LED having a slightly different colour temperature or brightness.

White/Light Spots On Screen

If you have white spots or very bright areas on your screen - then it's very likely that one or more of the small lenses that are glued to the front of the LEDs in your set has either fallen off or moved.

If this is the case then you can take the set apart, and re-glue the lens to the LED. We will warn you however that this is a very delicate procedure to get the lens lined up exactly and so that the light output exactly matches all of the other LEDs. If you are not confident then we would recommend purchasing replacement strips and swapping the strips out entirely - new / replacement strips come with the lenses already glued / attached so you will not need to worry about alignment.

If you wish to swap out the LED Strips, continue reading to the bottom of the page to find out how.

No Backlight

Depending on your type of set, this could be the result of a few different issues. The issue typically is caused due to one of these reasons:

• Faulty LEDs on the backlight strips, causing the backlight circuitry to shut down.
• Faulty power supply board, meaning that no power is being sent to the backlights.
• Faulty LED driver board (not all sets), meaning that no power is being sent to the backlights.

If you are willing to take your set apart then sometimes you will be able to diagnose these issues visually with very limited tools (this is not always the case).

Typically you will be looking for faulty / leaking capacitors on the LCD Power Board - although capacitors can sometimes fail and not show any visual signs. If you are able to confirm that the power board is operating correctly, then the next think to check would be the LED strips themselves. A quick visual check to look for burned or damaged LEDs may indicate where the problem is.

How To Replace LCD LED Strips

Warning: Disassembling your LCD set to get to the backlights is a complicated and delicate process, please be very careful when removing the LCD as it is very easy to crack it or damage the thin ribbon cables.

If you are looking for a tutorial for your exact model - we would suggest searching on https://www.youtube.com - there are thousands of tutorials for specific sets.

Generic instructions are below:

1. Place the set screen side down on a study table, with a soft towel protecting the LCD screen from damage.
2. Remove pedestal stand (if relevant) so that the screen sits flat on the towel.
3. Remove all screws from the back of the set.
4. Remove plastic rear cover from the back of the set.
5. Take detailed photos of all boards and cable locations, so that you can easily put the set back together once you've replaced the faulty LED strips.
6. Remove all of the individual boards, taking great care not to snap any of the plastic connectors or thin ribbon cables (if you are struggling to unclip some cables, search for YouTube tutorials).
7. Carefully flip the set, and remove the plastic surround keeping the LCD screen in place.
8. Carefully lift the LCD screen out of the set, and remove the LED diffuser sheets to be able to get to the LED strips.
9. Replace LED strips.
10. Reassemble set and test.