HP LP3065 black screen, LED lighted, USB works

[freddyfena]

Re: HP LP3065 black screen, LED lighted, USB works

Hi, well I wouldn't start doing any trouble shooting if I'm too uncertain. A full trouble shooting requires to disassemble a lot and put the power board "upside down" and connect everything, including shield/GND. But if you feel lucky one could just change the bad diode, read my post 03-09-2011, 01:24 PM, pict: Bad diodes.PNG. Also remember to look for obvious things like bad caps and burned components :-).
Good luck!

[freddyfena]

Re: HP LP3065 black screen, LED lighted, USB works

Well, I used ordinary screwdrivers to search and find the nasty clips that holds it together. Too bad I have already assembled it, so I cant provide you with any pictures. Just be careful, and use little force in the beginning.

[freddyfena]

Re: HP LP3065 black screen, LED lighted, USB works

Hi again!
I finally got the rectifier and changed it, but when I measured the 18V and 24V, I got about the same result. But then I thought why not connect my macbook to it and see? And IT WORKED! So lesson here is to connect everything when trouble shooting ;-)

Although I didn't get it to work on my HP(!) PC at all, I found out that it needs a dual link. funny that my macbook could drive it through the mini display port at 1280 x 1024. If I had tested it on my PC directly I would probably disassemble it and continue...

[freddyfena]

Re: HP LP3065 black screen, LED lighted, USB works

Well I´m still waiting for the component to arrive, I hope to assembly it during next week. I´ll write back soon.

[freddyfena]

Re: HP LP3065 black screen, LED lighted, USB works

I have been a bit busy lately, I have now asked of a sample of a UF1005. Thank you so much for all the help I have received, I love this forum :-)

[freddyfena]

Re: HP LP3065 black screen, LED lighted, USB works

Well the Zener diode seem to be OK.
the other D307 reads the same, so I will try to find a new one tomorrow.
I will measure the transistors later.

[freddyfena]

Re: HP LP3065 black screen, LED lighted, USB works

With out power I have measured the component in heat shrink tubing (a 0.33 ohm resistor) to 0.3 ohm. I have also measured all diodes I could see; all but two had 0.4 - 0.7 V. One, Z0101 is short circuited, 0 ohm and the other D307 (Besides L6598) gives 0.1 V and has 95 ohm, see picture. I've also looked after bad bad solder joints more carefully, but can't see anything bad. I'm not sure how to test the transistors....

[freddyfena]

Re: HP LP3065 black screen, LED lighted, USB works

Yes Pin 12 and STBN-24 seems to have a period of about 4 seconds
The two diodes have a resistance of 407 respective 403 ohms.

[freddyfena]

Re: HP LP3065 black screen, LED lighted, USB works

We use 230 V AC in Norway
I have measured on the L6598

Pin 1 = 0V
Pin 2 = 0V
Pin 3 alters between 0.4 V and 2.5 V
Pin 4 alters between 0 V and 2 V
Pin 5 = 0V
Pin 6 alters between 0 V and 0.39 V
Pin 7 alters between 0 V and 0.37 V
Pin 8 = 0V
Pin 9 = 0V
Pin 10 = 0V (GND)
Pin 11 alters between 0 V and 5.5 V
Pin 12 alters between 0.4 V and 11.4 V
Pin 13 = 0V
Pin 14 alters between 0.8 V and 7.3 V
Pin 15 alters between 0.8 V and 7.6...

[freddyfena]

Re: HP LP3065 black screen, LED lighted, USB works

Across the large cap I have 380 V
In: alters between 0 V and 5.3 V
5V: alters between 1.3 V and 5.3 V
Out1: 0V
Out2: alters between 0 V and 20 V
The IC is a L6598, See picture also...

[freddyfena]

Re: HP LP3065 black screen, LED lighted, USB works

Thanks, it's a LX3 camera :-)
So, now I have measured again:
I have connected everything without the chassis now.
The STBN-24V pin gives 5.1 V and drops down to 0V and up again to 5.1V, its period is around 5 sec.
VON is 3.3 V and VBR is 0V
Its the same result if I pull out the connector to the inverter board.

[freddyfena]

Re: HP LP3065 black screen, LED lighted, USB works

Here are the two connectors.
The pin "VON" is 3.1V see picture P1050133.JPG. VBR = 0V
I have connected all but the inverter board and when I measure the 24V it goes up to about 4 V and down to almost zero and up again (Guess I told a bit wrong in the previous post). And still no change with the inverter board connected.

I haven't measured the other connector (P1050146.JPG) when it was assembled because it is completely inside the metal box. If really necessary I will take the time to disconnect...

[freddyfena]

Re: HP LP3065 black screen, LED lighted, USB works

Maybe my mistake, I ment that I had measured it in the first post.
So: At first I measured the Inverter boards connector as all was connected.
and then I removed the PSU board and measured it by it's self. Both measurements gave the same result: 0V on the 24V. There is also another connector with 5V and 18V, but here only the 5V (for the USB) seems to be OK (3.1V on the 18V). There may be other powers/signals as well but I'm not sure what to expect to be correct.

[freddyfena]

Re: HP LP3065 black screen, LED lighted, USB works

When I connect only the PSU to 220V, I can only measure the 5V, (3.1 V on the 18V) nothing on the connector to the inverterboard.
Here is another picture.
Thanks so far...

[freddyfena]

Hi
I just got a HP LP3065 from work, because it's non working and out of warranty.
I have tried all 3 DVI inputs and I get no picture, the LED is lighted orange. The computer can sense it's presents and identify the screen. The USB-hub is working. I have googled but with poor results, seem like this is a rather good LCD monitor :-). I have measured the connector of the inverterboard, but it has almost no power, 3-4V somewhere, but no 24V. So I suspect the PSU has failed... for now. I don't see any physical damage or bulged caps. The PSU is a LITEON PA-3171-2-LF rev B. The biggest...

[freddyfena]

Re: Imac Isight G5 PSU repair

Hi
doanh, are you absolutely sure that only the PSU is bad? Because the mobo usually has whole bunch of bulged caps, I'm actually trying to repair a 17" model now and I have not less than 15 bulged/blown caps. I just got the Imac from a friend and I know it doesn't start and that this is a common issue, read more here: [url]http://jimwarholic.com/2008/07/how-to-repair-apple-imac-g5.php[/url]

RegardsRe: Imac Isight G5 PSU repair<br /> ...e mobo usually

[freddyfena]

Re: ACER AL2423W - no display

That is because I removed and put the transformer back, I and have not cleaned or tried to make it look nice ;-)

[freddyfena]

Re: ACER AL2423W - no display

Here are 4 pictures of my power board. I started with changing to those green caps......

[freddyfena]

Re: ACER AL2423W - no display

Too bad, thanks for your try. Anyone else have the possibility to get a circuit diagram? Or have some hint?

[freddyfena]

Re: ACER AL2423W - no display

Thanks so far, I have measured a bit on the primary side but can only conclude that the 230 V is being rectified to 330 V pretty soon. Before T2 there is only 330 V DC and after there is nothing, no DC no AC, i would expect 19V and 12V.
(Before T2 there is 110 V AC and 330 V/1000V DC and it is giving correctly 5V.)
So my conclusion is that there might be some component before T1 that is damaged. Does anyone have a circuit diagram for the FSP112-3F01?