Got this non-working Samsung model QM49R, like new (Aug 2019), plugged-in, after 5 sec power up (without pressing the power button) with backlight on but no start up sound, no image.
Hard to be power off by the switch or remote.
Pressed on remote control "EXIT" then "Left" and "Enter"...the front red led was blinking!
Restarted and I heard loud and clear ”Please select your language” message… but no image on the screen !!!
Next, I want to Reset EEPROM that means to short the VCC and SDA for 20sec.
On the mainboard (BN94-14556B) there are two chips IC1603_UT (W25Q80D) and IC1604 (W25Q40CL)...
I assume the first one is communicating on I2C protocol even is a serial flash SPI chip.
Please confirm if this is the right one !
I did find a mainboard spare part, exact part number as original, as per e-bay seller: brand new/unused ...receive it, replaced the old one, double check the connections, plug-in the AC power cord and... same issue: tv starts by itself, the display backlight is on with no image and same voice message to do the initial set-up !!
According with some similar service manual, after mainboard was replaced "please change the factory option as well"...but is nothing to see on the screen!
Ultimately, I tried to reset the EEPROM chip (IC801, ST24512) ... following the standard procedure, unplug the power cord, short SDA and VCC, plug in the AC cord, wait 30-45sec...during this time the screen and backlight are NOT turning on, remove the short, the tv is turning on by itself with same voice but no image !!! Should I wait more than 45 sec? Could be the display defective or different P/N ? Any ideas ? Can I connect an external monitor to this tv set (reading some EU models have this option to SCART connector...)