"Is it possible to recalibrate the input even with AV "failure" in service menu?"
I'm able to answer by myself to the last question: no, it's not possible, as the displays crushes whites from IRE 70 up.
Last week, I performed a full calibration of a Samsung PS50a456 (European version of PN50a450); I noticed that controls in user menu were a little coarse, preventing a perfect calibration, especially in low lights. So decided to give a look to service menu.
But I made a mistake (maybe a big one): entered WB calibration, than submenu "Calibration" that showed each possible source of the display followed by the term "success" (AV "success", component "success" and so on..). I had to exit this, for me, mysterious submenu but my finger was faster than my mind and I hit "enter", instead of "return".
So the TV entered a sort of auto calibration of AV source (I had my set top box on and connected via Scart to the display), going from low output to high output and vice versa; I waited for about 10 minutes, while the TV continued this sort of auto calibration, then stopped it and was displayed: AV "failure", instead of AV "success". Exited service menu, re entered my former calibration settings and, while other sources were OK, the AV source (set-top box) was completely out, in terms of colors, white balance, black level and white level (lot of solarization).
Is there any way to fix this problem (the set top box is a "Sky box" and only has a scart output)? Maybe I need to feed a particular signal during auto calibration, but what signal? Is it possible to recalibrate the input even with AV "failure" in service menu?
Thanks for your answers

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