I picked up a free hp f2105 lcd today. Its doing the thing where the back light will come on for only 2 or so sec. works fine otherwise and is in nice shape. It was already apart when i got it so that saved me some hassle. The first thing I did was do some research(ie googling) and found a post about unplugging a gray wire from the main inverter connector. And it actually fixed it until I put it all back together haha. So now I am after the cause of the issue. I have located replacement inverter boards but i don't really have the money to spend on one right now and would rather fix it myself. The caps are elite brand and seem fine but i do not have the equipment to test them. Where should i start troubleshooting. Or should I just pony up the ~$50 for the replacement board and save the hassle?
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Re: hp f2105 inverter
Welcome to the forums. I have one of these monitors (revived from the dead) and I think it's great. This was one of my early projects with the same symptoms that you described and I jumped in and replaced the caps because they were a crap brand even though there were no signs of bulging as you described. After re-capping, the symptoms were the same so I checked the bulbs. Indeed, I had a single bulb dead which was shutting down the circuit. I replaced the bulbs with similar ones and changed the connectors and it works perfectly. Long story short...check the bulbs. By the way, which wire did you disconnect...I can't tell from the picture. -
Re: hp f2105 inverter
I removed the gray wire that goes from the psu to the inverter board to make it work until it was re assembled.
Is there any way to test the bulbs to find out wich is bad or is it better to just replace all of them? Do you have a source where i can find replacements?Comment
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Re: hp f2105 inverter
Use a case CCFL/Neon case mod kit.Originally posted by turbostdThere are 10 kind of people in this world: those that understand binary, and those who don't.- ASUS ROG Maximus IX Code
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Re: hp f2105 inverter
Now iv'e done it I let out some magic smoke :X I was messing with this thing and actually got it to work and stay on for a bit by not tightening the screws that hold the inverter board down. I guess this means there is a bad solder joint? Well I put it all together and was using it for a bit when it went POP! sizzle.... I tore it back down and found a burn mark on one of the ccfl connectors
the middle one on the top is black and melted a bit now. What does this mean is bad?
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Re: hp f2105 inverter
It sounds like you have a short. Tightening the screw would ground the board. Is the burn mark at the connector or on the bulb end? I had a bad solder on the wire at the tube itself which was arcing. Someone like Plainbill is really good at walking you through the circuit. This is not my strong suit.Comment
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Re: hp f2105 inverter
freelander,
i need to replace the bulb on my similar lcd monitor.....but i am having trouble finding a replacement..........what bulb did you use and where did you get it? Thanks.Comment
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