26" Sanyo LCD DP26671 No Backlight

[Glitcher]

Hey guys I need a little help on this one. The TV is able to turn on but the screen is pitch black. I took a flashlight and shine it around the screen and I can faintly see the words "video".

This has a power supply and inverter combo.

[budm]

Re: 26" Sanyo LCD DP26671 No Backlight

Your board is not the same as the one Iowrk on, but look at the mian baord to see if it has K8L, if it does, disconnect it to see if the backlights will come on.
http://s807.photobucket.com/user/bud...15801085939669

[Glitcher]

Re: 26" Sanyo LCD DP26671 No Backlight

Doesn't seem to have that connection with this main board.

[budm]

Re: 26" Sanyo LCD DP26671 No Backlight

Check the voltage at that test point and ground (chassis), you must have the boards all mounted and connected.
Also check the blue fuse F3807 (7A 250V).

[Glitcher]

Re: 26" Sanyo LCD DP26671 No Backlight

The blue fuse seems good, continuity between both ends measuring 6.8V both ends when tv is standby and on.

Checking the test point, I'm getting 24.9V when tv on and 0V on standby.

[budm]

Re: 26" Sanyo LCD DP26671 No Backlight

"6.8V both ends" I would expect 24V on that fuse since it feeds the inverter power supply circuits. Let me trace the board again to make sure.
OK, never mind abut that reading, the fuse is in the primary side, so if you use the chassis as the Ground ref. point, the reading will be wrong. But since the 24V is working, that means the 24V power supply is OK, but the inverter may not be receiving the Backlights ON (BL_ON) on one of the pin of the black connector on the power supply board, the On command comes from the main board.
We do not have the pin out of the black connector, so it will be difficult to find out which pin is the BL_ON pin.