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Last week I was given an LCD monitor with what to appeared to be a bad backlight. The screen would come on for two seconds and then turn off again. After reading some (a lot) other blogs about backlights, I had come to the conclusion it was something with the inverter/psu unit. I proceeded to replaced all the “normal” capacitors that go bad, even though none of them looked bad. This did not solve the issue. I searched high and low for someone who had fixed this monitor. It seemed that there were some people who reported having this problem but either they threw the monitor out or send it in under warranty. I started searching for other psu/inverter units that were the same. I found nothing. I broadened my search only looking for boards with the model number “FSP060″. The inverter that came in the monitor was labeled as FSP060-2PI09. I was able to find something similar looking that was out of a Visio 22” LCD TV (VO22LFHDTV10A) the part number on that was FSP060-3L02 . I picked this up for $16 + Shipping ($29 shipped). The reason I went with this one is, because I was able to get it for cheap and it was the most similar one I could find to the original. Here are the two side-by-side. (Original on left)

When I got the new one I realized that they were not the same size, so that issue would have to be addressed later on. For now I needed to figure out if that would work. Other than the size of the unit the other main difference was the pinout connecting it to the main video controller board. The old one had 12 pins in a 2×6 connector the new one had 14 pins in a 1×14 connector.

I started evaluating how many of the pins were the same. It turned out for the most part only two were clearly different. The old one was supplying +5.2v while the new one was doing +5v. I decided that this was a tolerable spread. There were two of the connectors that didn’t match the two connectors on the new one. The old pins were a “PSON” and “O/F” and the new pins were “ION” and “VON”. The only way I could really tell which ones went to which would be to wire it up and try it out.

In my box of old computer parts I found two connectors that would fit into the new psu plug. Luckily, the ones I found were a 4 pin and an 8 pin which adds up to be 12, the amount of wires coming out of the main video controller board. I started cutting and splicing the ones I knew for sure that went together which were the GND, 5v, 12v, and ADJ. After those were all soldered together, I had to figure out were the other pins connected. I first tried to ground the ION and VON pins with no success. After that I tried 12V, which also did nothing. When I connected it to the 5v however, I got some power to the backlight. I now knew the the ION pin needed to be connected to a 5V source. I thought about connecting to another one of the 5v pins permanently, but that would mean that the backlight would be on as long as the power was plugged in. Next I tried the connecting the PSON pin to the ION and there was nothing. Finally I tried the ION and O/F and we had it! The backlight would turn off and and on when cycling the power button. I still didn’t (and still don’t) know what the PSON and the VON corresponded with each other, but they were the only two connections left so I soldered those two as well.

Now that I had the monitor working I needed to address the fitment issue. There were 4 main posts that held the board into place. Luckily the new board had nothing around the two bottom holes, so I was able to drill new holes for the posts on back of the LCD. The area by the top holes, however, was being occupied by many jumpers and resistors. I decided that it would be best to hot glue some cardboard squares to the posts, so the electronics on the board didn’t get shorted out by touching the metal posts.

Now I put it all back together and I now have a working LCD monitor.