How to repair an LCD flat screen TV that won’t turn on? I have a 55″ inch flat screen TV that is not working properly and would like to repair it. The TV works but I think maybe a board or a cap inside is bad. Can you give me some advice as to what may be the issue? I will explain what I have found so far. TV has power and it stays on standby just fine, the red light turns on when plugged in but no turned ON. Once turned ON, the light turns orange for a few seconds and then it goes to the ON green light. Sometimes it starts going only to orange but then back to the standby red light. The TV will work but only after turning it ON and OFF like 15 to 40 times. Do you think the power board or power supply is going bad therefore the TV will not turn on properly? Any help is appreciated.
How To Repair An LCD Flat Screen TV With Power Issues
We have seen many large flat screen TVs do this. It is usually one or more bad capacitors on the power board.
- A cap is a few bucks and easy to replace if you can desolder and solder.
- You need to identify the bad capacitor.
- The bad cap will look buldged out or extra fat and deformed.
- The small cross on the top of the cap usually splits when they go bad.
- (This is because of a chemical reaction in the capacitor that expands therefore leading to the buldging.)
- Find the bad cap and replace it.
UNPLUG THE TV FIRST… Then open the TV case carefully and gently. Gain access to the inside of the TV so you can see all the boards inside. Look at the capacitors on the power board for any signs of buldging. If you see no buldging caps then you may need to just replace the complete power board which are not expensive.
LCD LED TV Repair power boards
At times, caps don’t always bulge out & you cannot measure capacitance with a regular volt meter. You COULD order all the electrolytic capacitors you need for the TV power board. This would be time consuming and might not even work. A new power board would make the most sense. Need to find a special part for your LCD or LED flat screen TV? Here is a Parts Store for LCD TV Parts.
TV Power Supply: The power board converts the ac line voltage which is 110 volts AC to lower voltages that are required for the operation of the television, very important is the stand by 5 volts needed by the microprocessor to stay wake so when it receives a command such as power on to turn on the power supply, then the power supply generates the secondary voltages needed which can vary by television, some are 12 to 18 volts needed by the audio circuit and 24 volts supply to the inverter board and numerous other voltages.
LCD LED FLAT SCREEN TV power boards
Here are some videos for Repairing an LCD LED flat screen TV with power issues…
LCD TV Repair – No Power, Power Supply Common Symptoms & Solutions
How to Replace Power Supply
LCD TV Power Supply Tutorial Help for LCD TV Repair Fix
Element Hisense Dynex Insignia LCD TV Power Supply Repair Fix
Involves troubleshooting and repair of the power supply board
Testing LCD TV Power Supply Boards~STEP BY STEP
Need to know for sure if your power supply board is faulty before buying a replacement?
Easy way How to test Capacitors, Diodes, Rectifiers on Powersupply using Multimeter
Best Easy Way How to Accurately test Diodes, Capacitors, bridge rectifiers in TV power supply boards,
“how to use multimeter” to test or read TV parts in power circuit boards commonly in LCD, Plasma, DLP TVs
How to Troubleshoot an LCD TV
Three main ways to troubleshoot an LCD TV that does not require in depth knowledge of TV repair
Do you know of easier ways to diagnose and fix an LCD LED TV with power issues? Please leave a comment below.
I have a Samsung plasma 61″ it turns on I have sound just no picture.
I’ve checked capacitors don’t seem to be damaged.
Model PN60E55OD. Sn/ SNZ4SQ3CZD1001156H.
Can tv power supply boards exhibiting scorch marks under the transistors connected to a heat sink be repaired by just replacing the blown caps and transistor that went bad or will the entire board need to be replaced?
This is a Samsung which made a pop noise and now just clicks when one tries to turn it on.
Douglas,
It would be BEST to check with a Multi-Meter to find out first… but if you are unable, then the most likely board to fry from a lightning strike in your TV is the main power supply board as that is the first board in the TV to receive power. So that is the best guess but may NOT be the issue. Use a meter to be absolutely sure.
-RR
I have an LG 42 TV LB5600 and lightning struck near the house and the TV will not power ON. Nothing is burnt on the boards and the cord works. I have no meter to check the voltage but should i just replace the power supply board?
Hi dont know make of tv its 40inch and has these numbers on the back grt 12880610047 its has a blue light for power that comes on but the red light which is for the tv flickers about twice then goes back to the blue light no picture or sound thanks
I own a sony klv-26s400a series LCD tv. Recently my tv was not switching on, so thought of checking it. I have doubt on power supply and need some inputs on testing the power supply. I see that the fuse was blown and pcb near one of the switching transistor is dark, i am suspecting the switching transistor.
My question is after replacing the transistor how do i test it, I have only the power supply board and outputs connection to the other pcb are removed.
1) can we test the power board without connecting the load(the output to the other pcb)
2) can we see the output voltage at the connector without connecting the load.
3) is standby voltage 3,3 v is always available irrespective of power on switch.
4) there is pins saying power on do we need to short this pins to get the output voltage.
BP-Carbide,
If you replaced the power supply board and the TV will still not turn ON, have you inspected the ribbon cables to be sure they did not get pinched, damaged, or burnt when the TV popped?
Check all the other board to be sure of no damage or loose ribbon cables.
It has to be something besides the main power board obviously, so check everything once over and let us know what you find.
-RR
It just made a noise. No smell, or smoke. No signs of anything burnt inside.
It’s a Sharp TV, model number: LC-50LB150U
I ordered and installed a power supply board (715G5778-P02-000-002M) that matched the TV, but the TV still won’t turn on. No standby light or anything.
I’ve used a multimeter to check the connector and it is getting all the right voltages when it is plugged in.
Thanks for posting how to fix a flat screen TV with power issues. I should look back at this list of things that I should check for if my TV has a bad capacitor. Looking for a cap that bulging and deformed seems like a good way to find out the condition of the capacitors. I’ll also check for a split cap when looking at my TV before telling a repair contractor what the problem is.
BP-carbide,
What is the make and model of your TV?
Let us know and we can give you more info about what part to replace.
When you say your TV POPPED, did you smell any electrical smell?
Do you see any burnt residue on the inside of the T?
Have you checked all the caps on the boards?
Usually a POP is a cap popping in the TV on a circuit board.
-RR