I've repaired three TVs in the past year by myself by replacing the bulging/leaking capacitors, but this one seems to be a bit beyond that.
I have a Sanyo DP42848 TV that I purchased for $50 because the display does not power on. This is a backlight or inverter problem from what I can tell. It turns on, you have sound, everything works but you can only see the picture with a flashlight. The inverter PCBs are getting 24v from the power PCB. I've checked the fuses on the inverter boards and they are good.
I've read a few threads concerning this model TV here on the forums, and most are turning on for a couple seconds, then going out or turning off - mine does not do this. It turns on and stays on for as long as you'd like - you just don't get the CCFLs turning on.
I work at an electronics manufacturing facility, so testing the PCBs down to a component-level shouldn't be an issue. My knowledge and tools are limited, but what I don't understand, and what tools I don't have in my arsenal I could have one of my Electrical Engineering friends help me with (I'm just the I.T. guy).
When talking with my EE friend, we originally suspected the horrible solder joints on the inverter boards to be the cause of the backlighting problem. We cleaned up all the joints real good and touched up a few bad ones but the backlights still didn't fire up.
I have tested the inverter transformers (per https://www.badcaps.net/forum/attach...4&d=1350660859) and on the master and slave, the outboard is open while the inboard is not.
I've attached photos of the boards to this post, both with the flash on and off (flash washed out some parts, but without the flash the focus is fuzzy)
I have a Sanyo DP42848 TV that I purchased for $50 because the display does not power on. This is a backlight or inverter problem from what I can tell. It turns on, you have sound, everything works but you can only see the picture with a flashlight. The inverter PCBs are getting 24v from the power PCB. I've checked the fuses on the inverter boards and they are good.
I've read a few threads concerning this model TV here on the forums, and most are turning on for a couple seconds, then going out or turning off - mine does not do this. It turns on and stays on for as long as you'd like - you just don't get the CCFLs turning on.
I work at an electronics manufacturing facility, so testing the PCBs down to a component-level shouldn't be an issue. My knowledge and tools are limited, but what I don't understand, and what tools I don't have in my arsenal I could have one of my Electrical Engineering friends help me with (I'm just the I.T. guy).
When talking with my EE friend, we originally suspected the horrible solder joints on the inverter boards to be the cause of the backlighting problem. We cleaned up all the joints real good and touched up a few bad ones but the backlights still didn't fire up.
I have tested the inverter transformers (per https://www.badcaps.net/forum/attach...4&d=1350660859) and on the master and slave, the outboard is open while the inboard is not.
I've attached photos of the boards to this post, both with the flash on and off (flash washed out some parts, but without the flash the focus is fuzzy)
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