I was trying to reset the Pulse Meter and re-adjust the Panel-1/2 settings in the SM on an exceptionally old Pioneer LX5090 (51k power-on hours according to it's SM). I did this many times on much less aged specimens (with 10-20k hours) without issues. After following the usual workflow, I noticed the darkest gray shade showed up black with bright sparkles. I tried to adjust some other parameters but it didn't disappear. Then I went on and restored the old values of the parameters I don't usually touch (although I did this from memory, so I might have made an error). After that, I started going through all the built-in test patterns (masks) in various drive modes (60/72Hz) until I found one that made the TV turn off. After that, a blue light blinked when I tried to turn it back on with the remote (I didn't count the number of flashes). I unplugged the 230V power cord and tried to turn it on again. Now it briefly turns on but due to how the SM works on these devices, it immediately tries to display the same mask which causes an emergency shutdown.
I tried rapidly sending the FAY command immediately after powering it on (which should reset the mask setting and greet me with the SM's main page on black background instead) but I am not that lucky because the TV doesn't react but tries to light the screen up regardless (it becomes bright for a very brief moment before it shuts itself down).
I see two possible solutions here:
1: Some workaround to prevent the mask from activating on boot. This could either be like disconnecting some other board from the main board and entering the SM blindly (if that's possible) which should reset the mask, or
2: Figure out which board sends the emergency message and try to renew it (by replacing old capacitors, etc) or replace that board with another used part in a hope that the TV will be able to handle that test pattern without shutting down (at least long enough to process the FAY command and reset the mask setting).
Can I achieve #1 with something like reflashing the EEPROM? (Is a "clean" dump available somewhere?) Or is there some even easier solution, like some "pins to short on some board to power the screen up in some 'reduced' mode" (or any service mode which resets the mask settings)?
In case #1 is not viable, then how should I narrow the problem down to a boarad/IC?
But the #2 solution won't work in case I misadjusted some values and thus an emergency signal is bound to happen with every board/IC in perfect condition.) And #1 won't work if something got fried. Also, trying #2 could also fry something new yet again...
3: I also thought about replacing the entire main board but that's not cheap and this set is way too aged with 51k hours. And I am not sure if something else is "fried" anyway. (It's just my wishful thinking that the TV would still work with normal loads if the mask was removed, simply because the screen light up for a brief moment.)
I tried rapidly sending the FAY command immediately after powering it on (which should reset the mask setting and greet me with the SM's main page on black background instead) but I am not that lucky because the TV doesn't react but tries to light the screen up regardless (it becomes bright for a very brief moment before it shuts itself down).
I see two possible solutions here:
1: Some workaround to prevent the mask from activating on boot. This could either be like disconnecting some other board from the main board and entering the SM blindly (if that's possible) which should reset the mask, or
2: Figure out which board sends the emergency message and try to renew it (by replacing old capacitors, etc) or replace that board with another used part in a hope that the TV will be able to handle that test pattern without shutting down (at least long enough to process the FAY command and reset the mask setting).
Can I achieve #1 with something like reflashing the EEPROM? (Is a "clean" dump available somewhere?) Or is there some even easier solution, like some "pins to short on some board to power the screen up in some 'reduced' mode" (or any service mode which resets the mask settings)?
In case #1 is not viable, then how should I narrow the problem down to a boarad/IC?
But the #2 solution won't work in case I misadjusted some values and thus an emergency signal is bound to happen with every board/IC in perfect condition.) And #1 won't work if something got fried. Also, trying #2 could also fry something new yet again...
3: I also thought about replacing the entire main board but that's not cheap and this set is way too aged with 51k hours. And I am not sure if something else is "fried" anyway. (It's just my wishful thinking that the TV would still work with normal loads if the mask was removed, simply because the screen light up for a brief moment.)