Anyone has an idea what's going on with this TV?
IMO the mainboard is gone crazy.
The TV turns on and works for exactly 54s, picture, sound, inputs all ok. Then turns off after exactly 54s.
What I did so far:
1. Measured all PSU voltages, all good
2. Removed cable from PSU to Mainboard, backlight turns on and stays on. Put cable back in place.
3. measured BLU_ON, PSU_ON and OD_ON. BLU_ON goes off first, then PSU_ON after 50ms, the PSU shuts down
4. one at a time, removed LVDS, removed bluetooth module, removed Wifi module, no change. Put cables back in place.
5. Removed BLU_ON, PSU_ON, OD_ON and the four PWM signals from cable between PSU and mainboard, backlight remains on but picture disappears (mainboard shuts down) , need to power cycle to revive mainboard
6. put all signals back in place. heated whole mainboard, no change
7. freeze sprayed whole board, no change
The problem does seem to be related to either some watchdog function on the mainboard or maybe in its firmware loading process it gets to a point where there is a bug.
I can get into the service menu but all ER-counters are 0 except "power failure" which is at a fixed number of 116. There is a "debug" tab in the service menu but not sure what that could tell me.
Downloaded firmware update from the net (is from May 2020) but the update option in the main menu is greyed out. There would also be no time to update the firmware.
The new FW would be T-MST12AKUC 2230.0 while the currently installed seems to be 2204.3. So shouldn't be a problem of a recent automatic update, I guess. Is there a way to update FW starting directly from USB drive without going through the main menu?
I was unsucessful in finding a schematic for this board. I doubt it would be very useful anyways.
Thanks
IMO the mainboard is gone crazy.
The TV turns on and works for exactly 54s, picture, sound, inputs all ok. Then turns off after exactly 54s.
What I did so far:
1. Measured all PSU voltages, all good
2. Removed cable from PSU to Mainboard, backlight turns on and stays on. Put cable back in place.
3. measured BLU_ON, PSU_ON and OD_ON. BLU_ON goes off first, then PSU_ON after 50ms, the PSU shuts down
4. one at a time, removed LVDS, removed bluetooth module, removed Wifi module, no change. Put cables back in place.
5. Removed BLU_ON, PSU_ON, OD_ON and the four PWM signals from cable between PSU and mainboard, backlight remains on but picture disappears (mainboard shuts down) , need to power cycle to revive mainboard
6. put all signals back in place. heated whole mainboard, no change
7. freeze sprayed whole board, no change
The problem does seem to be related to either some watchdog function on the mainboard or maybe in its firmware loading process it gets to a point where there is a bug.
I can get into the service menu but all ER-counters are 0 except "power failure" which is at a fixed number of 116. There is a "debug" tab in the service menu but not sure what that could tell me.
Downloaded firmware update from the net (is from May 2020) but the update option in the main menu is greyed out. There would also be no time to update the firmware.
The new FW would be T-MST12AKUC 2230.0 while the currently installed seems to be 2204.3. So shouldn't be a problem of a recent automatic update, I guess. Is there a way to update FW starting directly from USB drive without going through the main menu?
I was unsucessful in finding a schematic for this board. I doubt it would be very useful anyways.
Thanks
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