I have a toshiba tv model #50L1400U. After the tv warms up the picture will flash every 3 to 4 seconds on all inputs. Should I replace the power supply, main board, or both? Thanks

SOURCE: toshiba 42hp82 plasma picture problem

Resetting the TV

Some TVs have a reset button. If available and accessible, try using the reset buttons before using the steps below. Using the reset buttons can saved time.
1. Unplug the TV power cord from the power outlet for 3 - 4 hours.
2. Unplug any connected devices (DVD, Set-top boxes, etc...)
3. Press and hold the TV power button for five seconds.
4. Plug the TV power cord back into the power outlet and turn on the TV.
5. Open the on-screen menu to confirm that the TV is responding again.
6. Turn off the TV and reconnect the devices.
7. Turn on the TV.

hope this may help;

Regards,
VOTIT

SOURCE: Power Supply Board for SAMSUNG 40" LCD TV Model LA40R81BX

You'll find some Samsung power supply boards here : http://www.usefulparts.com/index.php?main_page=index&manufacturers_id=11&sort=20a&filter_id=98&alpha_filter_id=0
but you have to open your TV first and find out model number

Ginko

• 19396 Answers
• Posted on Dec 06, 2010

SOURCE: I have a Toshiba 42hl67

Hi.

The point is that with LCD TV (which are very different from computer repair) you often need testing before finding the fault. In this case you have replaced amost everything, the fault then is either the T-con, the main boardm (which are only parts with panel and chassis that you have not replaced), or one of the parts already replaced that had failed because of incorrect installation procedure.

Since it is very easy to fry a board, and since a technician diagnosed the inverter (I assume that they tested the TV), testing will start right from the inverter. The inverter is tested reading DC in from main board to master, dc from master to slave, and AC high voltage out from slave, which hosts the oscillator section that should also be tested using an oscilloscope.
Since the TV is in forced standby (protection because the fault is detected), in order to get DC to inverter from main, the control line to correspondent DC voltage from PSU must be activated. The inverter voltage is the higher DC line from PSU. This is activated jumping the control line with the 3.3 or 5V low DC from PSU. In this way both PSU and inverter get tested. The procedure is also a superficial test for some main board functonalities. This kind of test is done with live power and involves testing high voltage lines. For safety reasons the operation must be done by a trained person.

The alternative is once again taking a chance and replacing main and T-con, but as said, that is not a good way of repairing a 42'' TV.

Here parts for this TV.

Regards.

Ginko.

SOURCE: Sanyo DP50747 Replaced Power Supply still not working

this issue is related to either the y sustainer and z sustainer boards, checking the fuses on the y/b will giving you a good indication, if they are open(bad) then you'll have a easy fix, if not, i would try replacing the y board first.

SOURCE: I have an RCA TV

The fact that the screen illuminates properly and does not stay absolutely pitch black means that the backlights are working properly.

A faulty LCD Controller Board (or TCon board for short) could possibly cause the symptoms you describe. The Tcon board is usually located under its own RF shield and will have a large braided steel multiwire cable coming into the bottom of the board and several flat ribbon cables connected to the top by little plastic flip up connectors. A replacement board can be purchased on Ebay for around $70 plus shipping. See the following link for one example:


http://cgi.ebay.com/LCD-CONTROLLER-V320B1-L01-C-RCA-L32WD12-/360142646595?pt=LH_DefaultDomain_0&hash=item53da2cad43


Just use your mouse to click on the link, which is the underlined and highlighted text just above. This will open a new web browser page automatically for you and allow you to view the item information at the website indicated.

Just don't buy any that say AS IS for their description of condition. That is EBay speak for broken.
Make sure they say TESTED FULLY WORKING in the item description.

The best way to be sure you are getting the right part is to open up your set and check the part number that is printed directly on the circuit board itself. Then look that part number up on the internet or type that number into the EBay search box.

Just typing in the model number of your TV will sometimes give you a few different part numbers so you have to confirm which part is in your particular set.

Make sure any part that you order online has exactly the same part number as the one you are replacing. Sometimes it it just the last few digits that are different and it can make a difference.

Here are some links to some excellent LCD Troubleshooting Guides from another expert (BUDMRTN) that you can read through and get an idea of the LCD repair process:


http://www.fixya.com/support/r5093881-lcd_flat_panel_tv_troubleshooting_guide

http://www.fixya.com/support/r6150077-basic_lcd_monitors_troubleshooting

http://www.fixya.com/support/r7406380-tv_training_manuals

http://s807.photobucket.com/albums/yy352/budm

http://en.wikipedia.org/wiki/Capacitor_plague

Please leave a Thumbs Up rating on his pages if you find his guides helpful.

Please comment back here to this page if you have any details to add, have any questions, have difficulty accessing the links, or just require further general assistance and I will respond as soon as I see it.

Thank you very much and good luck.

Joe.