Any Panasonic Viera lcd tv experts?

[Gdog215]

Hello, I have a tc-L37s1 with a steady red standby light that won't turn on.
No video, audio or backlights. When pressing power I get a click and a red light no blinking and a black screen. First Panasonic I've tried to fix.

[budm]

Re: Any Panasonic Viera lcd tv experts?

Service manual:

You need to find out if the main board is sending the PS-ON signal to turn on the power supply board or not, so look for the power supply on signal pin on the connector between main and power supply board.
BTW, are you trying to fix it down to component level (including SMD type), or changing boards?

[Gdog215]

Re: Any Panasonic Viera lcd tv experts?

Either or as the boards for this tv are still kind of pricey, probably will use just as a spare room tv. Because the resale will probably be low. The component level fix will seem like a challenge I might try though.

[budm]

Re: Any Panasonic Viera lcd tv experts?

Well download the service manual and read it, that will be the starting point.
So you do have tools, correct?
How much times and studying are you willing to spend?

[Gdog215]

Re: Any Panasonic Viera lcd tv experts?

A lot as I’m laid off as a systems pos pc technician looking for full time work, I’ve already fixed 3 TVs this month, waiting for my friends income tax so I can unload. Got the tools meters and rework station and am fascinated with these damn TVs. Will study the service manuel. Thanks Budm

[Gdog215]

Re: Any Panasonic Viera lcd tv experts?

Upon researching this tv I found that there is a small sq101 bulb on the power board. I read disconnecting the 2 backlight connectors from the power board than powering on the tv. Looking at this bulb seeing if it lights up or not would determine if the problem were the backlights or power board itself. Mine did not light up, so I'm thinking issue with the power board. Also noticed a big yellow component on the power board looks slightly burned. Maybe a transformer?
What do you guys think? Maybe buying a cracked power board same part number for cheap and replacing this part? Included pictures

[R_J]

Re: Any Panasonic Viera lcd tv experts?

Is the fuse that supplies the inverter section ok?

[Gdog215]

Re: Any Panasonic Viera lcd tv experts?

Yes the fuse tested good

[budm]

Re: Any Panasonic Viera lcd tv experts?

https://www.badcaps.net/forum/attach...8&d=1524071481
That is power transformer for switched power supply that will be turned on when PS-ON is present.
What DC Voltage when measure right between the two legs of the main filter cap (the big large cap laying on its side) when power switch is activated?
BTW, you have 3 power relays (RL101, 102, 103) on that power supply/inverter board, do ALL three of them click on at all?

Panasonic N0AE3FJ00002 Power Supply for TC-L37S1
http://www.shopjimmy.com/panasonic-n...pply-unit.htm#
Pictures provided by shopjimmy.

[R_J]

Re: Any Panasonic Viera lcd tv experts?

Have you checked the voltages on P2, page 28 ofthe manual lists the pin# and what the voltage should be. when the power button is pressed you here the relay so standby voltage must be ok at least. Have you tried shining a flashlight at the screen to see if there is any image (you may need to press the menu button to get an image if its not on a working input)

[Gdog215]

Re: Any Panasonic Viera lcd tv experts?

I really need to brush up on my meter testing skills on a live tv, as I’ve been shocked before while playing around with plugged in tv power supplies. This tv has been sitting in my basement for some years as career got in the way. But a hint when I first bought the tv was told that it needed a new transformer. Will try to check the flashlight trick and check for the menu and get back to you guys.

[Gdog215]

Re: Any Panasonic Viera lcd tv experts?

Went to check voltages on p2 but noticed when the tv is plugged after awhile clicks and the red light blinks 13 times. The service manual says 13 blinks is emergency sos comm error between ic 8007 and ic 1102, check point a board. Flashlight trick pressing menu still black screen. Used my Apple TV with screen mirroring through iPad no picture or sound. Unsure measuring voltage on p2 connector, never saw a connecter like that on a tv attached as picture. Also tried to test voltage on the big cap dc voltage was 516 volts if I did it correctly.

[Gdog215]

Re: Any Panasonic Viera lcd tv experts?

Update it was the main board 13 blinks per service manual comm error 8001 ic chip
Thought maybe bad cold solder joints on chip. Applied flux to sides of ic chip than heated it up for 10 minutes evenly. Powered it on and boom. Working tv

[Andrew F. Ali]

Re: Any Panasonic Viera lcd tv experts?

Good job!!!

[tvdoctortv]

Re: Any Panasonic Viera lcd tv experts?

I got Panasonic TX-LR32E3 with 13 blinks. Heating up the processor with hot air gun ( 400 Celcius for 40 seconds) did not make any difference). Do I have to heat it up for a longer time? Trying to fix A-board to a component level. Also read that the flash memory may be the culprit. Any help in solving this problem is greatly appreciated. A link to a service manual, troubleshoot guide, etc. for this model will be very helpful. I got this TV as a gift and would really want to upgrade my CRT to a HD standard.
Measured PS voltages are 5,7V, 16V, 24V. On A board I got sub 3.3V, sub 5V, sub 1.5 V, sub 1.2 V - all OK. CPU is MN2SW0177. It looks like I don't have 2.5V and 12V out from DC/DC converter IC4150 BD81021. I could not find the datasheet on this IC. My intuition tells me it's either CPU or Flash memory, but would love to confirm it, if possible. Thanks for any help.
P.S. TV behaves as follow. After plug into AC no light comes on. When pressing "turn on" button the green light flashes for about 10 seconds then goes to steady green, but nothing comes up on screen, no BL neither, no sound. It stays like that for 5-7 minutes, then red 13 blinks comes up.

[tvdoctortv]

Re: Any Panasonic Viera lcd tv experts?

BudM, would you please help me with a link to a service manual or troubleshooting guide for Panasonic TX-LR32E3. Thank you

[yohnsee]

Re: Any Panasonic Viera lcd tv experts?

Sorry to bother, but you may want to have a look at this manual:
https://elektrotanya.com/panasonic_t.../download.html
Here the model nr. ends with 30 not with 3, see for yourself if it can be useful.

EDIT: As always, pcb modell numbers and display type would help us a lot.