Not so long ago, my 2008~2009 VIERA TV decided not to power on stable. Sometimes it would give me 3 clicks instead of the usual 2, and then blink red 10 times.
When I took it to a repair shop, they asked quite a lot to replace the whole power board because these models are not supported by Panasonic anymore. Thus, I decided to give it a shot on my own.
DISCLAIMER: In no way the author of this post may be responsible for anything, including injury or death, or other loss or damage that happened due to following the instructions listed in this post. You are doing this all at your own risk. There are lethal voltages above the mains voltage inside plasma TVs, and so you must have enough qualification to perform these modifications to your plasma television set. If you are not sure you can do it, take your TV set to an authorised Panasonic service engineer.
So, first, I opened up the case. The power board can be easily spotted if you have enough electronics experience 🙂 It’s yellow and has some huge scary caps on it as well as some impulse transformers and fat wires, not to mention it has mains wires going straight to it and it’s located in the centre.
First of all, get a 10-watt concrete resistor of about 500 Ohm (that’s what I used at least) and connect one of it’s leads to ground by attaching it to one of the screws that hold the PSU board’s heatsink to the plasma. Then, using a heavily insulated wire connected to it’s other lead, carefully touch the points labeled 赤 and DISCHARGE on the PSU board. This should make the board a bit more safe and discharge those huge 450V caps (I was still hit while reworking it, however — seems like smaller caps need to be discharged separately, so take extreme care!). Then, remove the top 2 fans out of your way, label all the connectors somehow (and take photos for good measure) so you don’t mix them up, and disconnect them. Unscrew the heatsink from the plasma, and you are left with a bare PSU board on a heavy aluminium plate, and an empty space in the TV.
Flip the board over and unscrew the plate from the PCB. After doing this you will be left with a lot of screws — make sure not to lose any.
After doing this, take the bare PCB to your workspace. Find the two small sub-boards with the TEA1611 chip. Desolder them and take them out. They might be stuck to nearby components by some sort of gummy sticky thing, so be careful. These boards supply the panel’s X and Z(Y) axis sustain voltages, and contain a very failure-prone component we shall replace.
Note: they might look the same, but they have different Panasonic P/N so they might actually differ. I’m no authorised Panasonic service engineer so I can’t tell if they do. So better take care not to mix them up. Rework them one by one for good measure.
Here on the photo you can see the board that causes the problem, with the pencil pointing at the failure point. It’s so small, yet so troublesome!
So, time to go to the nearest electronics store and get a 0805 size 1uF 50V rated SMD capacitor. You can try installing a bigger one, or even a solid-state one like they put in computers — if it’s polar, the negative pole points to the top of the board and the positive looks to the bottom (where the pins are). I can’t say this is accurate because I only saw this in someone else’s TV, better get a non-polar one.
Be warned: these things are tiny! Look at the photo above with pencil for scale, or this:
I couldn’t take photos of the process because it would be too hardcore. Some people replace the TEA chip too, but I didn’t have any at hand, so I decided not to do it.
I had no experience with SMD prior to this so the cap ended up a bit skewed, but as long as it didn’t short anything and did make good contact I wouldn’t mind xD
Reassemble the board in reverse direction, put it back in, connect everything, close the cover.
Plug in the mains and wait for an explosion.
Hmmm, no third click?
TV, a bit later: click
Reach out for the remote, hold Power.
Turn it off and then on again — while previously that would cause 3 clicks, now it works again!
A new TV would cost about ≥ $1,000, whereas this repair was around 50¢!
If that helped, enjoy your new old VIERA panel!
Now if only I could fix the HDMI port, burned out by the poorly built Ufanet HDTV set-top box…
Categorised in: HowTo's