HP W1907 2 seconds to black

[budm]

Lamps look good, but the wire came right off when pull on it.
Notes: All the lamps light up even the one with bad wire.

[budm]

Re: HP W1907 2 seconds to black

Part ii

[G3n1us]

Re: HP W1907 2 seconds to black

I'm not exactly familiar with this monitor, but riddle me this: how can a disconnected lamp light up? It doesn't make a whole lot of sense.

But if the lamps turn off after two seconds, then probably you're overloading the inverter or the power supply. Unfortunately i've got no other recommendations than try with a fresher set of lamps. Or perhaps a few shorter lamps (they draw a bit less current.)

[Rtech]

Re: HP W1907 2 seconds to black

This is a common fault with this model,usually the Top B/Light,and normally it is either one or both of the Lamps or the the Return wire/s that cause the fault.The fault being that all the lamps switch on initially but then the Screen goes Black,a typical '2 seconds to Black' scenario, although it can be longer han the 2 seconds.the Channels the Lamps are fitted into are some of the narrowest I have seen, the wires seem to be of poor quality, and lead free solder is used,the latter in some cases giving poor joints.If you add those reasons to the fact that heat rises, then you can also see that it is normally the top Set of Lamps where the faults lie,and I think that Budm,did not mean that the faulty lamps stayed on permanently.

[budm]

Re: HP W1907 2 seconds to black

@G3N1US, I already fixed the broken wire, monitor is working now, I had three monitors with bad wires yesterday, DELL, SONY, HP.
See what kind of lamp failures I deal with here:
http://s807.photobucket.com/albums/y...klight%20lamp/

The lamp will light up for second if the wire is real close to the lamp terminal, remember that the start up voltage of the CFL is about 2000V, tha is enough to jump the small gap or stray capacitance, see picture of what high voltage can do.

I used test lamp for testing inverter, that is the first thing I do when I have 2-second to black, same a lot of time.
There were no wire slack at all the way they put the lamp assembly together, so the wires were pulling on the connection and it barely make the connection, so it lit up and goes off, 2 second to black.

[killian6pk]

Re: HP W1907 2 seconds to black

@G3N1US, I already fixed the broken wire, monitor is working now, I had three monitors with bad wires yesterday, DELL, SONY, HP.
See what kind of lamp failures I deal with here:
http://s807.photobucket.com/albums/y...klight%20lamp/

The lamp will light up for second if the wire is real close to the lamp terminal, remember that the start up voltage of the CFL is about 2000V, tha is enough to jump the small gap or stray capacitance, see picture of what high voltage can do.

I used test lamp for testing inverter, that is the first thing I do when I have 2-second to black, same a lot of time.
There were no wire slack at all the way they put the lamp assembly together, so the wires were pulling on the connection and it barely make the connection, so it lit up and goes off, 2 second to black.

Damn Bud you must work on 100 monitors a day going by your picture #4 in your photo bucket array. Now I know who to contact when I need a lamp holder.

[HappyBob]

Re: HP W1907 2 seconds to black

Thanks for all the guidence. I had the 2 seconds to black on HP 1907W, that I tracked down to burned/broken return wires on the ccfl. After I removed the ccfl assemblies I resoldered that ended the 2 seconds to black.

I tested with the lamps exposed, the power/inverter board and the video board laid out on the bench. I did not connect the LVDS nor did I have any video input connected. The lamps would now stay on for about 70 seconds.

I ordered the ccfl assemblies and am anxiously waiting for those. The caps on the power/inverter board all look good, so I wasn't planning to recap.

So my question is this: Is the 70 second to black screen expected when there is no video input or the LCD panel is not connected. Should I just recap because I can while disassembled?



I ordered

[smason]

Re: HP W1907 2 seconds to black

Damn Bud you must work on 100 monitors a day going by your picture #4 in your photo bucket array. Now I know who to contact when I need a lamp holder.

Wow, no kidding. I have 2 sets of lamps for testing, that's it.

[budm]

Re: HP W1907 2 seconds to black

@happybob, do you have the monitor connected to running PC? otherwise it will go into standby mode.

[HappyBob]

Re: HP W1907 2 seconds to black

@budm, Thanks again for all the pixs. I'll try the video input after I relamp, expect those parts in a couple of days.

[chris g]

Re: HP W1907 2 seconds to black

Well i have the same issue with my 1907 i had a little luck then it ran out! I switched the sockets on the Blue/Black CCFL wires and it work for about 20 min then that's it they went out.

[ndoggfromhell]

Re: HP W1907 2 seconds to black

I've got three w1907's. I replaced capacitors and output transformers. Now the monitor will work fine unless it gets warmed up and you reset it. If it's hot and you power cycle it, or you change inputs the lamps will go out and you can only faintly see an image. Thoughts?