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SONY BRAVIA KDL-46EX705 - BAL Board replacement not working / green and amber li

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  • #1
    Level 2  
    Sony Bravia KDL-46EX705



    Hi, I'm having a problem with my Sony KDL-46EX705. I bricked the original BAL Board by unintentionally pressing the Enter Button whilst being in the Service Menu. It said WRITE in a red font. I turned the TV off quickly (which was very stupid). Then I turned it back on and it still worked but then I unpluged the TV and from there on the Screen remained Blank. When pressing the Power Button the Green led lights up and thats it. After a few minutes the TV then resets itself and then the Backlight comes on and the Tcon power gets switched on.

    So I ordered a used BAL Board, although knowing of the Panel ID encryption. On some forums i read that this encryption pairing can be redone by installing the "new" used BAL Board and performing a Software Update via USB. My thought was that the encryption pairing to the panel should be stored on the 24C32 EEPROM connected to the MIMAS Co-Processor, because the MIMAS Co-Processor is directly connected to the I2C lines of the T-CON. My thought was that if the SW Update doesn't work, I could swap the EEPROM and maybe also the MIMAS from the bricked board to the "new" used one, to get the TV to work.

    But sadly all attempts failed to get the TV to work.

    The old bricked Board hangs somewhere in the Bootprocess of the Mainprocessor (NEC MC-10161F1-420).
    I have come to that conclusion because, the clock of the NAND memory stops after a few seconds and by compairing it with the new used Board NAND Clock I noticed that there is stuff going on for much longer. Also it doesn't turn on the regulator for USB 5V.

    With the new used Board the TV immediately starts flashing the green and amber LED's simultaneously which according to another Forum means that the BAL Board is in Bootloader Mode and waits for an USB Stick with appropirate SW on it, to perform a USB SW Update.
    However I put the SW on two different USB Stick's, both formatted FAT32 and followed the instructions on SONY's website for the SW Update.

    I couldn't get it to perform the Update. One of the two USB Sticks that I tried the proceedure with has a LED indicator for data trafic and it appears that the BAL Board reads the Stick but doesn't find the file.

    It might be that the Board expects a NVM Config Update File but I don't have any information on how to update these 1-881-636-22 boards after changing the BAL Board with a used one, other than loading the SW Update file from Sony's Website onto an USB Stick und inserting it into the TV.

    I hope somebody can help me and give me some informations on how to get a used BAL Board to work inside of a different TV.
    It should be possible.

    Best Regards