Chosen Solution
Sanyo DP42D23, power and sound but no picture. Picture is visible with a flashlight. 120V is good. I’ve checked DC voltage at K702, There is 12V at the pins required. This is about as far was I’ve gotten with my limited ability. Any help is appreciated. Ted Update (11/15/2019)
Hi @nict , Couldn’t find a service manual for the TV but you’re description indicates a problem with the LED backlighting. Found this link which may help to get you further on to resolving the problem
@nict it always pays off to give all the voltages. Remember that this is a backlight issues so you need to get the voltages for BL-On (~3.3V)and BL_DM as well. Then measure the voltages on your backlight connectors. If all of those check out your TV is having issues with the backlight array. If the voltage do not check out, you are having trouble with your power board.
Pin 1-3 68V Pin 5-7 100V This is not an answer but just an augmentation to @jayeff answer
I don’t know if you have fixed your tv yet, but my issue was a burned out led in one of the strips. I didn’t have the led/backlight testing tool so I used this video to diagnose which strip was faulty. https://youtu.be/4pK6o2DMLWQ
