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What Causes a TV Backlight to Fail? (And What to do About it)

Having recently experienced a failed backlight on my TV, I was feeling frustrated and looking for answers. After doing some research, I discovered a number of potential causes and solutions for a TV backlight failure. In this blog post, I will be sharing what I learned, as well as other tips and tricks that I discovered while researching the topic. So, if you’re trying to figure out why your backlight isn’t working, you’re in the right place. Let’s take a look at what causes a TV backlight to fail and what you can do about it.

Generally, sudden power surges, overheating, and faulty LED bulbs can cause the TV backlight to fail.

Cause of TV Backlight FailurePossible Fixes and Prevention
Power Surge1. Perform a power drain by unplugging the TV, holding the power button for 30 seconds, and turning it on.
2. Use a surge protector to prevent future issues.
Overheating1. Unplug the TV and allow it to cool down for 15 minutes.
2. Clean the vents with compressed air or a vacuum cleaner.
Faulty LED BulbsReplace the LED bulbs with new ones of the same amperage and voltage.
Water Damage1. Unplug the TV and dry out the electrical components using silica gel packets.
2. Clean the components with isopropyl alcohol or compressed air.

What Causes a TV Backlight to Fail?

LED TVs quickly became a famous choice among homeowners. While they’re modern sources of entertainment, they’re not impervious to backlight malfunctions. 

Here are the common issues that cause a TV backlight to fail, including their possible fixes:

  1. Power Surge

Typically, home appliances can cause a sudden power surge. The most common culprits are conditioners, washers, furnaces, dryers, and heavy-duty power tools.

Once a power surge happens, a voltage of electricity higher than the recommended operating range passes through the circuit. 

As a result, the high electrical current can damage the circuits attached to the electrical components. Unfortunately, these electrical components include the backlight. 

That said, the power surge can burn out the LED lights and cause a short circuit in the LED driver circuit as well. Consequently, the power won’t get into the LCD panel. Although a small power surge rarely results in device failure, it can cause permanent damage to the backlight. 

You can fix the issue by performing a power drain. First, you’ll need to unplug the TV. Press and hold the power button for 30 seconds to drain the residual power. Lastly, plug the TV back in and turn it on.

Moreover, you can prevent future power surges by getting a good quality surge protector

  1. Overheating

Another factor that can cause your TV backlight to malfunction is overheating

Usually, high temperatures are a result of high brightness and high voltage. If the LED bulbs become too hot, they might burn out or force the screen to automatically dim its lights down.

To fix the overheating issue, you can unplug your TV and allow it to cool down for at least 15 minutes. You can also check the vents along the back of the sides of your TV screen. These vents are responsible for creating an airflow and cooling down the device.

Therefore, if the vents accumulate dust, it can disrupt their function. In this case, you can use compressed air or a vacuum cleaner to clean the gunk out.

  1. Faulty LED Bulbs

Most LED bulbs have a limited lifespan. Although they usually last up to ten years, some of them inevitably become faulty with frequent usage. 

Since LED bulbs are connected in a series, a defective bulb can affect the rest of them. In such cases, your TV screen becomes dim or starts having dark spots.

Hence, if you’ve been using your TV for quite some time, you might need to replace the LED bulbs. Luckily, LEDs don’t come at a steep price. Plus, replacing them doesn’t require expertise on your part. 

To replace the bulbs, use a screwdriver to take the screws off the back of your TV. Depending on the model, your TV should have at least 15-20 screws in total. Then, unscrew the metal sheeting covering the internals.

Next, take off the LED panel and the frontal housing. Access the backlight by taking the bezel that holds the backlight diffuser. Now, you can start removing the LED bulbs and replacing them with new ones. Make sure that the new LED bulbs have the same amperage and voltage. 

Lastly, reassemble your TV.

In addition, if you’re not comfortable replacing the LED bulbs on your own, you can always reach out to repair professionals.

  1. Water Damage

Electronic devices are susceptible to water damage. It causes a short circuit in the circuit board, including the metal pathways. So, if your TV comes in contact with water, it can lead to backlight failure.

To prevent further damage, unplug the TV immediately from the power source. Then, dry out the electrical components. You can start by unscrewing the case of your TV to expose the circuit boards.

Next, put silica gel packets on the circuit boards. You can also remove the boards from your TV and put them in a bag with silica gel packets. Let them sit for at least two days. Allow one more day if your area has high humidity.

Afterward, you can use a vacuum cleaner or compressed air to dry them out. You can use a brush dipped in isopropyl alcohol too. Once you’re sure they’re completely dry, you can reinstall the boards on your TV.

Moreover, if you think that the process is too complex, you can let TV technicians have a look and fix the issue.

Wrapping Up

So, what causes a TV backlight to fail? Typically, the main culprits are sudden power surges, overheating, faulty LED lights, and water damage.

Generally, you can replace the LED bulbs yourself. However, if you’re not comfortable with a little elbow grease, you can always contact repair professionals. 

Read more: What can I wipe my TV with?