HP W2207 no screen no power buzzing!

[selldoor]

Re: HP W2207 no screen no power buzzing!

Hi - what make / series of caps did you use?

Have you tested the small yellow torpedo fuse - at the top in your second pic.


EDIT - Also top right corner there are 2 smd fuses looks like a G on them- have you tested those?

[mgaa80]

Re: HP W2207 no screen no power buzzing!

Hey, thanks for answering :-)

The 2 SMD fuses are ok..ich checked them and they both are ok, checked this with my continuity tester. Also they show 0.1 ohm each.

The yellow fuse above the pink resistor is also good, but shows 10.1 ohms.

I went to an electronic shop we have over here called 'Conrad' and bought the capacitors. They are 105° Low ESR (of course all matching uF numbers and voltages) from 'JackCon', 'Yageo', 'Richey' and 'JH'. Some of the capacitors on the board had 125° - but the electronic store only had 105° - so I bought them - will exchange them as soon I get the monitor running.

Maybe some useful background info:
The gentleman I bought the monitor from said the monitor began to have short blackouts (picture went black for 2 seconds, but came up immidieately after that) - until one day the monitor didn't turn on at all. I also tested the panel with a controller board from a samsung monitor & the backlights went on...so I'm more or less sure that the panel itself is ok.

Maybe you have another idea?

Thanks for the reply!
Br,
Matthias

[selldoor]

Re: HP W2207 no screen no power buzzing!

10 ohms is usually considered too high for a good fuse - can you test the voltage on each side with negative meter lead on ground screw. Just check it is a fuse - i cant read the board description. Perhaps see if there is any voltage on the 2 smd ones.

U101 and U202 look almost ok as they are voltage regulators the results should be steady!! can you test your meter on some other things batteries power supplies etc
The other probably isnt getting a supply voltage so may not be bad.

Can you carefully check the voltage on the BIG cap should be around 325vDC and hold on there a few seconds to see if that varies.

Also can you get hold of a 0.5 to 1k resistor? or a 3v battery like a cr2032 or 2 1.5 batteries.

[mgaa80]

Re: HP W2207 no screen no power buzzing!

Hey :-)

the label above the yellow fuse says 'f802' and the Board itself is a ILPI-029 REV. A 2006.12.20

Tested my multimeter with a CR32 Battery - showed a steady 3.102 volts. Also used another multimeter on the power board -> fluctuating voltages.

Also on the yellow fuse
Left side: 6.9-7.6v
Right side: 3.6-5.9v

The big cap shows 314v (steady)

On the SMD fuses are no further voltages, only label FS101 and FS102.

BUT here it comes:
This time I connected the power cord to the power board as my PC was off (no noise) and because it's 1:30am over here and there hardly is any noise :-) around I hear VERY quiet strange sounds from the board and this noise is correlating to the fluctuation of the voltages. I hear a quiet 'click' from the board and as soon as its 'clicks' the voltages drop and go down. I attached a sound file to this reply. I think this is also correlating to the blinking of the LED...seems to me that something is trying to generating power, but can't - then fails and tries again..and again..and again...

Does that help?

Thanks!
BR,
Matthias

[selldoor]

Re: HP W2207 no screen no power buzzing!

OK - something else to try to clear up one small point.
This is from Davi.P's post regarding the 0.00 voltage on regulator.
It has lost something in translation but he is trying to say: with it all connected up
and on connect up the USB from your PC to the USB IN on the back of the monitor, then
test the voltages again at the regulator and also the fuses ( they may be to protect the circuit from an incorrect USB IN connection)
I dont know how difficult it might be to do that?

Also can you check the soldering on the caps your replaced and just check that are all
in the right way round.

[selldoor]

Re: HP W2207 no screen no power buzzing!

Next test - probably not really relevant but gets it out of the way.
No power to the board meter on ohms 2000 test across pins 7 and 8 on each of the
inverter transformers.
Just to check have you had the lamps plugged in whilst testing did they ever flash at any point and related to that what is the part numbers of U501 and U502

[Davi.p]

Re: HP W2207 no screen no power buzzing!

Yes U113 is much probably powered from the pc usb port, you must test the psu 5v output that's the only supply output (well i don't know the meaning of sense +/-) to see if it fluctuates too. Test it with psu connected and then disconnected..

[mgaa80]

Re: HP W2207 no screen no power buzzing!

Thanks again for all your help, I did the following:

1st try:

FIRST I connected a USB cable to my PC, THEN I connected the power cord to the power board. The PC found a standard USB Hub and installed the drivers.
Then I measured the voltages again, ground was pin 11 of the 14-pin power board connector.
Voltages are as following (ALL STEADY NOW NO MORE FLUCTUATING AND THE STRANGE SOUND IS GONE):

U101
AIC
1084-33PM
Pin1: 0v
Pin2: 3.28v
Pin3: 4.52v

U102
AC
1084-18
0707BL
Pin1: 0v
Pin2: 1.8v
Pin3: 4.52v

U113:
A1
AS1117L-33
80652 84
Pin1: 0v (0v with USB cable disconnected and power connected)
Pin2: 3.26v (3.28v with USB cable disconnected and power connected)
Pin3: 4.5v (4.9v with USB cable disconnected and power connected)


SMD Fuses: 4,50v
Yellow fuse: Left 4,5v - right 7.15v


To double check the measurements I did a 2nd TRY and this time I accidently pluged in the power cord first and after that the USB -> voltages are fluctuating again (with USB cable connected!) and the PC keeps connecting and disconnecting the USB Hub infinitely (strange sound is back).

If I do it 'correct' (first USB cable then power) I can remove the USB -> voltages differ a little bit but remain stable & strange sound cannot be heared. So it seems to me (in order to get the voltages stable) you have to plug in USB first and then power up - after that you can disconnect USB...voltages reamin stable.

Soldering on the caps is good...I'm sure that can't be the issue (also with old caps it had the same behaviour). Positions are good, too - all marks of the negative side goes to the mark on the board.

The next test with ohm on the two 'SPW-080 LSE T13CH B': Ohms on 2k and it tells me .474 for the first and .486 on the second - measured between Pin 7 and 8.

Label on U501 and U502 is '9971GD 704106'

The backlights of the panel are ok - tested them with a board from a samsung monitor - and they both light up correctly. When I powered on the monitor is does absolutely nothing, no backlight is on (not even for a second) and no OSD is visible - nothing...just dead...except the blinking LED...but that blinking is also not a 'straight' blinking...the LED turns on and then it seems as it's losing power and then slowly fades out - until a few seconds later it comes up and dies again in the same way.


Does anything I said help?

THANKS again!
Greetings from Germany!

[selldoor]

Re: HP W2207 no screen no power buzzing!

Well we are building up a picture - pity it is not on the screen
I am still not happy with the yellow fuse - voltage should be the same on both sides.
It will say on it what amps it is and possibly the voltage. for testing replacement doesnt have to be exact must be same amps and voltage must not be less -but 12 or 24 v should be ok as you measured 7.5v.
The inverter transformers seem ok (within 3%) just

[mgaa80]

Re: HP W2207 no screen no power buzzing!

Hey :-)

First good news...exchanged that 4a fuse with a 3a fuse 12v and the Monitor is powering up!

BUT all I see is white...no OSD no picture from PC. Doublechecked the connector cable from video board several times...all ok.

Connected every cable...but only white. When I connect a DVI cable the monitor turns black (as it recignizes that) and after that it's white again...

Any ideas?

Thanks much - again!

[Davi.p]

Re: HP W2207 no screen no power buzzing!

Unfortunately you forgot to do my test.. the test of the 5v output.. it seems the psu goes in protection, anyway it's the same as one of the 2 readings on yellow fuse but i don't know which and overall why voltage on fuse is so strange.. you say left/right for the fuse.. if is referred to your top picture so left is the valley (to the output connector), in any way try to desolder one leg of it and test the other leg..

[Davi.p]

Re: HP W2207 no screen no power buzzing!

You wrote when i was writing.. ok you must measure newly the yellow fuse..
"Connected every cable...but only white. When I connect a DVI cable the monitor turns black (as it recignizes that) and after that it's white again..."
turns black means black with backlight visible or not?

[mgaa80]

Re: HP W2207 no screen no power buzzing!

Hello everyone,

sorry for my unclear expressions - was a little late last night :-)


So what I did: I replaced the fuse & today I measured it again - now with my new 3A testing fuse in it has stable 5.18v on both legs. When I remove the fuse the voltages begin to fluctuate again.


When I reassemble the monitor now & connect it to power it will take 3 seconds and the backlight comes up (power button LED also on) and as soon as the backlight comes up the screen turns completely white - so like it would display a completely white screen.
When I connect the DVI cable the display turns black for a moment (backlight stays on) and then comes up white again.

It seems to me that now the power is ok, but the signal from video board is defective and the video board only sends out white pixels to the panel. Or the panel itself is defective - but I don't really believe that...

Checked the connector from video board to panel several times, replugged it...nothing..only white.

Same situation with the USB cable connected etc.

Thanks much :-)

BR,
Matthias

[budm]

Re: HP W2207 no screen no power buzzing!

You need to check the SMD fuse on the T-CON board of the LCD panel assembly, there should be either 5V or 12V which is supplied by switched transistor on the logic board.

[mgaa80]

Re: HP W2207 no screen no power buzzing!

The only fuse I found on the T-Con Board was the one in image 2 - it was ok, showed 0.4 Ohms. Attached pictures of the T-Con board.

BR

[selldoor]

Re: HP W2207 no screen no power buzzing!

Budm was asking what was the voltage on the fuse.

Other possibilities for checking are the "0" resistors - like R24
Just test for continuity like a fuse.

[mgaa80]

Re: HP W2207 no screen no power buzzing!

Hi,

I used again pin 11 of the 14 pin power board connector (don't know if that is correct...but I didn't know better) and measured 0.42v at the fuse (guess that is either a little bit low or I measured incorrectly with wrong ground) . Fuse itself is 63v.

Checked all resistors etc. - on some my continuity tester made a sound - on some there was no sound - but indicated something on the display. In the end there are the following components, which were completely dead - no sound and no indication on the display:

r1
c6
c42
r49
c202
c32
c26
c27

tried every one of them several times..nothing...

Do I need to replace them all?

Thanks much!
BR,
Matthias

[selldoor]

Re: HP W2207 no screen no power buzzing!

You have been busy
What are the numbers on the R1 and R49

[mgaa80]

Re: HP W2207 no screen no power buzzing!

Yes - you could say so :-)

I think on both its '103'


BR,
Matthias

[Davi.p]

Re: HP W2207 no screen no power buzzing!

testing all capacitors in continuity mode is an unuseful test, and also test all resistors is too long, on the main/scaler board near lvds cable there's Q101 and the near 2 transistors, one of them has a 5v on at least 1 pin, test which is and after test the other 2 pins.