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Απο το service manual βρήκα την λύση ευχαριστώTry this: http://www.dvxuser.com/V6/showthread.php?330180-Yellow-Triangle-Exclamation-Error
It seems to be a common problem after accessing the service menu on a Panasonic camera and you can find quite a lot of other threads on the subject by using google.
Here is another: http://blog.lymanlime.com/2013/08/03/panasonic-dmc-gf3-service-menu/comment-page-1/
You could also see if you can download a service manual for the GX80.