SAMSUNG UE40H7005 - no picture but backlight and bootlooping

[olegeisler]

Hi

Have this 2015 40" SAMSUNG UE40H7005 - see pictures attached.
Owner really wants THIS TV fixed... But really has no value...

Symptoms : No picture ( and no sound ) - but backlight OK, seems to boot-loop though, backlight on for approx. 15 seconds, then off one second - and repeat indefinitely.

Sanity check of voltages seems OK, heatsinks on both mainboard and T-con heats up. Mainboard is BN94-07352J

Unable to find manual / schematic, and very little information in general.

Is it just a corrupt NAND / bad mainboard - so I should just forget it, or does anyone have a hint ?

[R_J]

Re: SAMSUNG UE40H7005 - no picture but backlight and bootlooping

Try disconnecting the flat cable between the main board and t-con board, If the tv stays on, re connect it and try disconnecting one of the flat cables between the t-con and the panel. Try one then the other one. Connect and reconnect cables with power off.
If when the t-con is disconnected it still reboots, try heating the heatsink where the large bga chip is located, It could be a bad bga connection.

[olegeisler]

Re: SAMSUNG UE40H7005 - no picture but backlight and bootlooping

Thank you

Disconnecting the MB>T-con cable status :

- Current consumption decreases
- No backlight ( explains the creduced current consumption )
- Still boot looping

I guess bad mainboard, will try to reflow main CPU tomorrow, unless a better suggestion arrives here.........

THANKS !

[olegeisler]

Re: SAMSUNG UE40H7005 - no picture but backlight and bootlooping

CPU now reflowed - still bootlooping, but no backlihght.

Will give the bad news to the owner, and this one will go to scrap...

THANKS for helping out.