What should the input voltage be at? Right now with the backlights flickering I have constant 21.4VDC, is that enough or is that low? If the problem is in the backlight inverters do you replace the master or slave or both or how do you know? Any insight would be helpful.
a 6ya Technician can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US. click here to Talk to a Technician (only for users in the US for now) and get all the help you need. Goodluck!
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
First check if you have on screen menu and if the problem is still there if you change input source and cables.
If TV has no backlight on all inputs, then it is either inverter not supplying power to the backlight system, or the LCD panel itself. The inverter or the parts connected to the inverter are common cause for the problem. The LCD panel is not a common fault. When problem is the panel the TV is not worth repairing.
When there is an inverter problem the fault is not necessarily the inverter. The technician needs
to test the parts to find out what part is responsible. Testing is done
tracking voltage from PSU to inverter. Voltage to inverter is usually
supplied by the higher VDC line from PSU. Here broad description of how to test the three
parts: Before proceeding...
Here replacement parts for most flat panel TV models:ShopJimmy.
You are right ,the problem is in the backlight. There's a loose connection in the connector of the backlight to inverter or driver.The backlight have high voltage supply,so if the coonector is mildly loosen,it may cause of voltage drop produce and spark and over heat the connector,and totally result of loose connection.So the things you can do to fix the problem ischeck the connection of the backlight.Open the back cover and look the board,located at the center part.It has a metal cover in the board,remove the cover and check the connector of the backlight,Resolder and tightly press the connector to the inverter or driver.It is usually happen to the backlight of the LCD TV.Just fix the connection of the backlight.Try my suggestion and procedure,.Hope it will help you..Thanks..
Problem is inverter, backlight or PSU. The backlight lamps that illuminate the LCD display are flashing. This creates the "kind of strobe" effect that you see. There are several possible causes for the problem.
The lamps themselves are defective. The lamps do not fire up completely and keep flashing. The lamps are not sold alone but they are part of the LCD display. If the lamps are gone the TV is not worth repairing.
The inverter is the high voltage board that supplies the backlight lamps. If the inverter is defective it can still be replaced. Testing is done reading DC in, checking high voltage out, and using an oscillator to test the phase of the AC out signal generated by the inverter oscillator section.
PSU or main controllers may be defective. This will less common in case of flashing back-light. Test this if the inverter is OK and if the problem is DC voltage input to inverter.
Go check the backlight inverter lamp, replace if busted. This can be found when you open the back of your lcd and manage to get access to it. The backlight inverter lamp is located at the upper and lower part of the screen. Go check also the inverter board, the one that suppply high voltage to inverter lamp, see if this ballast transformer are not burnt out. The
input voltage of the inverter board is 24vdc the output is 250v ac..The
voltage input terminal of the inverter board usually creates a loose
solder. Use a soldering iron to resolder them....
This lamps are
available online to order at shoppejimmy.com
This is a common problem on these plasma TV's. The problem resides in
the high voltage boards known as the X and Y Sustain boards.. You can
purchase them here for a very reasonable price: http://www.discount-merchant.com/Y-SUSTAIN-FOR-42-PLASMA-TV-PN-6871QYH036A-p/sku9510.htm
The above link is to a Y-SUS board. The X-Sus board is often the 2nd cause of failure and can be found here: http://www.discount-merchant.com/X-SUSTAIN-6871QZH041B-6870QZE017D-6871QZH052D-p/sku9509.htm
test which board is failing, you need to check voltage input to the
YSUS board first... Input should be 120V from Power supply, output
should be above 250V.. Do this test with XSUS disconnected. IF 250+V
exists, then XSUS is damaged. If not, then the YSUS is the faulty part.
This failure could be due to a backlight inverter board or the power supply is not providing the 24 volts to it.
The way to fix it is by measuring the voltages from the power supply to the backlight inverter board, if the voltage is present then the backlight inverter board is defective and will need to be replace. If the voltage is lower then 20 volts, then is a power supply failure. Click here to find the backlight inverter board.
Let me know if you need further assistance. I repair power supplies for all LCD models.
Apple doesn't provide voltage information for the Inverter Board. If you are getting external video then check to see if there is a dim (un-backlit) image on the display to ensure it is a backlight problem. If so then the chances are good you have a failed inverter board.