Asus VE205 .... 2seconds to black

[hiperco]

Re: Asus VE205 .... 2seconds to black

BTW, this isn't really an ASUS problem, its an LG problem (the maker of the panel). The part number of the panel is LM200WD1 TL C1 or LM200WD1(TL)(C1) or LM200WD1-TL-C1.

[hiperco]

Re: Asus VE205 .... 2seconds to black

Same problem here. I'm not going to bother to fix it, anybody need some parts from it?

[Phydoux]

Re: Asus VE205 .... 2seconds to black

Hmmm. I just got one from a friend. I will have to check this. Hopefully that's the same problem.

[Woolley]

Re: Asus VE205 .... 2seconds to black

Yes, thanks I thought it smelled like a short.

[swgaspidey]

Re: Asus VE205 .... 2seconds to black

thank you

[budm]

Re: Asus VE205 .... 2seconds to black

http://lcdparts.net/howto/selectccfl.aspx
http://lcdparts.net/howto/troublesho...sktopCCFL.aspx

[swgaspidey]

Re: Asus VE205 .... 2seconds to black

Update i replaced just the top cfl from lcd parts.net (quick shipping) and put it back together powered it on and IT WORKED wahoo. I will add that the bulbs are way fragile and putting all the layers to the panel back together and correct was not a task i enjoyed quite tricky but did it and have a happy friend with a working monitor. Thanks for this forum and all the helpful people here

found the same problem could you send a link to the replacement so i can repair mine.

[bluewhale32]

Re: Asus VE205 .... 2seconds to black

Update i replaced just the top cfl from lcd parts.net (quick shipping) and put it back together powered it on and IT WORKED wahoo. I will add that the bulbs are way fragile and putting all the layers to the panel back together and correct was not a task i enjoyed quite tricky but did it and have a happy friend with a working monitor. Thanks for this forum and all the helpful people here

[budm]

Re: Asus VE205 .... 2seconds to black

That the burnt wire symptom, very common due to poor soldering workmanship.
I would inspect all the wires, also pull it slightly to see if it will come right out.
http://s807.photobucket.com/albums/y...klight%20lamp/

[bluewhale32]

Re: Asus VE205 .... 2seconds to black

I know this thread is old, but this info might help someone else. I just received this same monitor from a friend it had the exact same symptoms as this guy did. push the power button had a brief flash of the pc desktop then dark, with a flashlight the PC desktop is seen just no backlight, power button led stays blue, after reading thru this forum i came to the conclusion it must be a bulb or inverter issue so after taking the screen apart and looking at the cfl's i noticed where the cfl connects to the tube whoever assembled the screen missed putting the tape over the corner where the wires meet the bulbby about 1/8" inch but just enough to cause the wires to short to the case i included a couple pictures (not very good but you will get the idea) i am going to order the cfl from lcd parts.net $14.95 so a fairly cheap fix (I hope) if i do not wreck the thing putting it back toghether.

[Welchs101]

Re: Asus VE205 .... 2seconds to black

it has been a while but i wanted to post an update. My neighbor gave me this monitor because it did not work. They bought a new one and let me keep this one so i removed the AO4614 devices from the circuit board to test them.

I removed both AO4614 devices.

I tested both using the link provided. In diode check mode.
For the N-channel device. I placed black lead on source and red lead on gate. I let it sit there for a few seconds. THen i placed red lead onto the Drain lead. The voltage measured 0.2V for a split second then decreased to almost zero. I reversed the leads and then did the same thing for the p-channel device.........same results.

I repeated the above process for the other AO4614 device and got the same results.

I guess this monitor is headed to the scrap pile unless someone has something else to try. I did want to provide an update in case this helps someone else.

[retiredcaps]

Re: Asus VE205 .... 2seconds to black

Any ideas on where to find a replacement part?

Many sellers on ebay.com.

[Welchs101]

Re: Asus VE205 .... 2seconds to black

i could not find another DMM so i think i am just going to try and take the IC out.

I did have a question though. If it is bad...........i looked online to find a replacement and .........i couldnt find one.

I checked digikey but they dont have any all they have is a AO4612 but i am not sure this would work. Any ideas on where to find a replacement part?

[Welchs101]

Re: Asus VE205 .... 2seconds to black

interesting........never thought about using another DMM. Let me see if i can find one............if that does not work then i may just ahve to remove the IC from the circuit.

thanks for the ideas.

[PlainBill]

Re: Asus VE205 .... 2seconds to black

anyone have any thoughts?

The AO4614 is a complementary pair of enhancement mode mosfets. What the big words mean is it contains one N-channel and one P-channel mosfet.

The test you are doing is for an N-channel mosfet; for a P-channel you would reverse the leads, and should get a similar result.

The fact that you get a brief reading on the first IC indicates it is working; there are several reasons you might not get a reading on the second IC, one of which is it may be defective. Another possible reason is the components driving the gate are turning it off quickly.

The best approach is to remove it from the circuit board and test. A second approach would be to rig up a tester which would allow you to maintain the voltage on the gate while checking the source-drain voltage. That could be as simple as a second DMM with diode test mode.

PlainBill

[Welchs101]

Re: Asus VE205 .... 2seconds to black

anyone have any thoughts?

[Welchs101]

Re: Asus VE205 .... 2seconds to black

is there some way to test it in circuit .........maybe while its powered on? To see if the device is working as it should?

[Rtech]

Re: Asus VE205 .... 2seconds to black

just maybe they need to be out of cct.

[Welchs101]

Re: Asus VE205 .... 2seconds to black

hi,

ok. i followed the directions of the link.

on diode check mode:NPN device
On say one of the IC's i put the blk lead to the source S1 and then touch the gate G1 (red lead) for about 2 sec then place red lead onto the drain D1. The voltage reading starts out at ~ 2V then increases until i guess it maxes out the diode check meter at ~ 2.5V.

I then repeat this on the other IC-4614. However, on this one i can get a reading once i place the red lead onto the drain. I go back to the first IC and try and repeat the procedure and i cant get a reading. If i wait a while and repeat the procedure on the first IC i can sometimes get a reading like i did the first time. But i cant get a reading on the 2nd IC no matter what i do.

Is this the only way to check the IC? I dont read any shorts as best i can tell.

Have not checked P-channel devices yet.......wanted to make sure i was doing it correct first.

[Rtech]

Re: Asus VE205 .... 2seconds to black

Although the resistance readings look ok, they still do not confirm for certain if they are working.They are complimentary mosfets,and need to be tested to see if they do switch on and off.It may be worth a try doing that using the diode test function on your meter,hope the following helps, if you are not sure what to do.The system shown still applies to your mosfet drivers even though they are not 3 pin devices.
http://www.4qdtec.com/mostest.html