Hi, all! First off, I want to thank everyone for making this such a great resource for learning and assistance--several others have had similar problems with this very same monitor, so by reading through those old threads I was able to take my diagnosis/troubleshooting at least this far (and found the schematic too!) Basically, I have a 2005FPW whose backlight started to fail a few months ago; at first, simply powering down the monitor and turning it back on would make it work again for a little while, but soon the screen would remain dark even as the power LED indicated the monitor was on. I knew virtually nothing about how monitors worked at the time, (and only a little more now ;x), but I remembered reading that when monitors failed thus, it was often simply a matter of replacing a couple of blown capacitors, so I decided I'd try to fix it myself. Upon inspecting the monitor's guts, no obviously bulging capacitors were visible, but the problem (or part of it anyway) was obvious: one of the 6 transformers that drive the backlight CCFLs had clearly burnt out, discoloring the surrounding board. (VERY similar to what's seen here: https://www.badcaps.net/forum/showpo...91&postcount=6) My first thought was, "Hey, I have a ton of spare inverters from broken laptop screens--why don't I just use one of those to drive the CCFL in place of the one that burnt out?" Taking a multimeter to test voltages on the board, There was immediate arcing between the probes and the chassis. After removing the shorted transformer, this is no longer the case, and I can use the DMM to probe points on the board without visible arcing. I was then going to hook up my replacement inverter to make sure it would drive the CCFL whose transformer burnt out, but noticed that it appears the leads from the CCFL itself appear to have arced, as the black plastic around the LCD has melted, exposing the lines (as well as the insulation of said high voltage lines), which leads me to believe hooking up another inverter would not cause the lamp to light, but just start high voltage arcing across the wires before it got there, maybe even destroying the new inverter. Basically, I realized that what I had ASSUMED to be the CAUSE of the problem (i.e. burnt transformer) could in fact have been a symptom of another problem (i.e. arcing HV wires going to CCFL). At this point, I need the insight from someone who understands how these things work better--what do you think is going on here? What would generally cause these symptoms? Is it possible that melted transformer really was the root cause of the problem, or is it more likely the arcing wires of the CCFL CAUSED the transformer to melt, or is something more complicated going on? If the bulb itself were dead, could that cause the wires to heat up, arc, short, and melt the transformer? Any insight would be greatly appreciated!
Thanks,
Nico
Thanks,
Nico
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