Guides and support for various TV brands and styles.

2644 Questions View all

Why is LCD TV backlight flashing?

Samsung LN-T4065F LCD TV 40"

The TV is 10 years old and has 5700 viewing hours.

The backlight is flashing on and off at a rate of about 3 times/sec. You can see a video of it here:

This used to happen periodically then go away overnight. Now it's not going away.

How can I debug if this is an inverter problem? I have a multi-meter. Or should I just buy the $17 inverter and hope for the best?

Answered! View the answer I have this problem too

Is this a good question?

Score 0
Add a comment

1 Answer

Chosen Solution

The backlight inverter is damaged. Needs to be replaced. Requires soldering. You could send the board off to a board repair shop in your area or mail in

Was this answer helpful?

Score 2


What kind of soldering? Videos I've seen show that replacing the whole board is basically plugs/wires.


You could do that. Would be much easier


Did some multi-meter tests on the inverter. Couldn't find any problem. I'm just going to spend the $17 for the new inverter board and see if it fixes it.


Ok. Let us know if you need anything!


New inverter fixed it!


Show 6 more comments

Add a comment

Add your answer

Matt will be eternally grateful.
View Statistics:

Past 24 Hours: 4

Past 7 Days: 8

Past 30 Days: 39

All Time: 230