DELL 2007WFPb with 2 seconds to black

[hkjinlee@gmail.com]

Greetings,

My DELL 2007WFPb stopped working properly from yesterday, which I bought almost 6 years ago. I googled and got here to find lots and lots of priceless information from others. Thank you for those who shared all the experiences.

Symptom)
- The screen shows without problem only for 1~2 seconds from being switched on, and goes to black right away.
- Shining flashlight to the screen reveals it is actually showing the produced image by PC, so the problem may be with the backlight.
- USB port has no problem

Brief diagnostic of inverter board)
- Disassembled it and checked all the capacitors, but they don't have visible leakage or something
- Checked three transformers: all three show almost the same resistance around 1.04KOhms. (Between pin#1 and #8, #4 and #5 accordingly)

I suspected one of these transformers would have gone, but they look like being OK. Attached photos of inverter board and PSU. Do you have any idea what I should do next? Thanks in advance.

[stj]

Re: DELL 2007WFPb with 2 seconds to black

6 years old - probably the tubes are worn out.

cfl tubes have a rated life of 50,000 hours.
6 years = 52,560 hours.

not that i trust those numbers - i'v seen tubes go after only a few years.

[bammbammfran]

Re: DELL 2007WFPb with 2 seconds to black

I agree with STJ on bulbs
Especially since it looks like they STUFFED 3 next to each other at each side of the screen... TOO MUCH HEAT there even when they only use two !!
They did this same crap with 3 bulbs on the 21" gateway and a few others

If you do not have a bulb tester and If you have another working used 19 or 20 inch panel around (17 should also work), you can plug that working screen into 4 of the plugs of the inverter (2 on the one side and two on the other side of the inverter) then use just two of the original screens bulbs at at time also plugged in to help you tell which may be bad.
might take some plugging and unplugging of different ones at a time to try to figure out which ones are causing issues

Don't plug the wide 30 pin cable into the rear of the screen .This should make the screen almost white and will allow you to see which lights are actually lighting.
pink light or darkness on one side of the screen would mean the bulb you just checked is bad.

[stj]

Re: DELL 2007WFPb with 2 seconds to black

fit an led kit!

[hkjinlee@gmail.com]

Re: DELL 2007WFPb with 2 seconds to black

Thank you for the advice. I thought I might buy a used inverter kit from taobao(something like eBay of China), but the CCFL looks like the one to blame. I'll give it a try and report the result.

[budm]

Re: DELL 2007WFPb with 2 seconds to black

You can make a couple test lamps:
https://www.badcaps.net/forum/showthread.php?t=19987