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My name isXXXXX am an Authorized Servicer For Panasonic,
Have you Ever had the Unit Cleaned, If not it is Recommend, This error is coming up because the unit is sensing a slowdown in air flow.
If You can remove the back cover the filter is located near the lamp but in many cases it requires the light engine to be removed in order to reach this filter.
You could remove the lamp and run a vacuum in the light holder this would pull some of the dirt free and hopefully allow you to resume function, but the filter will need to be cleaned and you should schedule its cleaning soon,
If you wish to clean the filter yourself you will need the service Manual, as removal of the light engine is let just say... Fun, yeah let say really fun. I hated trying to remove this engine the first time, it is not as clean cut as you would think as they hide screws EVERYWHERE.
Most shops Charge Around 120-175 for a cleaning and this is probably your best bet for such an expensive television.
If you do wish to try and repair this yourself i will be happy to help you locate the service manual. Let me Know.
If you have anymore questions or need clarification, Just Ask.
Hope this Helps,
You will need the service Manual and a second set of hands,
The service manual is available from Panasonic but they most likely will not provide to a consumer but you can try if they do it is a pdf and should be a small fee:
Or you could Download the manual from Service manual.net (this is a popular website but i have not used them)
I did the Foot work and found it avail on the site Here:
As for actually do this i can tell you this is a big job to get the engine in your hand so if you can get to the filter without removing the engine it is recommend you don't, You have to check the manual to find out how far you have to tear down the set to get to this point though.
Do Not Open the Engine itself, there are no filters in it and only trouble can come from it, the engine is a module with at least 20 glass mirrors and dicronic glass pieces in it and if one shift just a little bit the alignment will make you pull your hair out. The dust in the engine is better left alone. Just clean the set, the fans, the filters. The filters can be washed either by hand or in a washing machine safe delicates bag. Depending how clean you want it if you just want to replace the filter the part number is XXXXX the manual and the part can be ordered from www.encompassparts.com (use the guest login, if you cant find the part on the site just call the 800 number they will sell you the part).
Hope this helps,