20 Most Recent Samsung LN-R408D 40 in. LCD HDTV Questions & Answers

Take out the back panel and smell to trace what part is burned. Then check the high voltage circuit near the 120 volts. After the transformer, should be 380 volts AC. After the ratifiers, should be 390 volts DC - by checking at the capacitor as Samsung uses 100 uf at 450 volts. If not, change the capacitor to a higher rating like 350 uf at 400 to 450 volts.

My Mom's LNR408D also had sound but no picture. I was able to fix it by soldering in a jumper wire across a blown (1.5A ???) SMD picofuse on the "T-Con" board.
Consider attempting this ONLY if you: 0) Know enough to avoid the potentially fatal High Voltage parts of the power supply board!!!
1) Are a fearless hackazoid 2) know what you're doing with a soldering iron and teensie SMD parts 3) are gonna throw the busted thing out anyway so you have nothing to lose and won't be sad if you screw something up.
4) Know enough to avoid the potentially FATAL High Voltage parts of the power supply board!!!!!


This board is at the top center under a close fitting RF shield. The suspect part was labeled "CP" on the board and marked with "P" on the part. It is visible above the right-center of the connector from the main board. An ohmmeter showed it as open, so I bypassed it with a jumper wire from connector VIN to the hot side of C13. One image shows the suspect part and the jumper in place.


The other shows the TCON board placement top-center (under its RF shield). With care, it seems possible to test the fuse and put the jumper in place without removing the shield. (Obviously don't touch anything else with the VOM leads!)

Thanks to ZORBUS and Steve's TV and Electronics for the idea.
http://www.avforums.com/forums/lcd-televisions/892447-no-picture-but-got-sound-my-samsung-lcd.html
http://www.gesda.com/transformer/Fall08_files/Page336.htm
Steve C

Ur LCD inverter is dead,needed replaced.

The part labeled cp with a p on it has a black burn mark in the middle of it on mine!

Here's a story and source for KL15L5R1:http://blog.coppelltvrepair.com/2012/11/kl15l5r1-blown-on-dyp-50w2-from-samsung.html

no, the board it is on is sold as a unit---I have seen several techs try to replace the socket---there are some sites on the internet that stock by model number all the boards Google Samsung boards/parts.The only other option I see is connect the set via another input like component--that connector and the board are history.

try to play DVD movie or video when the problem still there the possible cause is T-con board if no vertical lines when you play DVD your tv is good your problem is on the loose connection

Unplug the TV from AC mains wall socket, and re-plug it back after 30 minutes or so. This must make a hard reset to this set.

First of all look for any loose contacts in power outlet or jammed buttons on control panel or on remote.There are dry solders, leaky/dry capacitors in the power supply or other parts of the board. A case to be handled by a qualified service technician.

Please follow guidelines in operation manual, step by step.

I'm willing to bet you have a backlight problem. Turn on the TV, take bright flashlight and shine it on the screen. Do you see the faint image???

look for bad capacitor on power supply , if there is not bad capacitor the problem may be the siganl pcb

After you are sure you have hooked up the receiver to the TV properly and with the proper setting in the menu, if you are still having problems then you need to change the main board (the one with all the jacks on it). You will have to take the back from off the set. You will have to get the number from off the board itself and it should start with BN94-. Do a search on ebay with the part number or go to shop jimmy.com for price and availability. Also try to google search. The board is easy to change just unplug and unscrew from the panel.

Try unhooking the LVDS cable from the controller board and see if it does the same thing. If so you need to replace the LCD panel.

It sounds like this is a problem with the inverter boards on the LCD panel. Unfortunately the inverter boards are usually only available with the whole LCD panel and the only way to fix it is by replacing the whole LCD panel. This is the most expensive part of the TV (about $1000) and you will need to take the whole TV apart in order to replace the panel. A new TV of similar make and model will usually be about the same price as the repair.