Solved No Power Problem In HP L1706 (PX849A) LCD Monitor
This Monitor came in with no power problem and found the main fuse 3.15 amp open circuited. As usual one has to find out whether other components have short circuit or not before you put a new fuse and retest the set. After scanning all of the primary and some of the major components in the secondary side of power supply i could not locate any shorted components. Placing a 100 watt bulb across the fuse and noticed that the bulb dims down and the big filter capacitor voltage did not drop even though the power jack already been removed.
Since the start up resistors are going to the power IC SG5841SZ (SMD IC) I suspect that this IC could be faulty causing the filter cap voltage remain high. Finding from my spare part compartment could not locate such part number thus i use SG6841SZ SMD IC as replacement to try it out. Before i put in the new IC, i did search from the internet and compare both spec and found that both of the IC’s were not much different from each other.
So the result was the LCD Monitor power came back a life after the replacement of the SG6841SZ IC and a fuse. This HP L1706 Monitor use some of the part numbers such as :
BIT3713 (INVERTER IC), 40P03GJ (FET), 2761I (Power FET), 817B (Optoisolator IC), 1506 (Voltage regulator IC) and AZ431 (Adjustable Precision Shunt Regulator IC). Please jot down in your diary book that the SG5841SZ can be replace with SG6841SZ.
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admin
December 25, 2009 at 2:07 am
Hi Charlie,
Guess you need to open up the Monitor and begin to look for any bad e-caps or even dry joints at the high voltage transformer pins. Sometimes it could be the problem of bad backlight too.
Jestine
Aye Thein
January 15, 2010 at 10:57 am
1 of the monitor was no LED light. Another 1 monitor was display a few mintutes
after power "on".
admin
January 16, 2010 at 4:16 am
HI Aye,
The first one you need to check for bad components in primary side. The second one you need to check the backlight or even bad e-caps.
Jestine
Ali Nawaz Wattoo
January 19, 2010 at 1:59 pm
sir my tft have a problem. problem is this when i give power to tft it will no work and stay in stand by mode. i have decided to repair it from technician but he theft its high voltage cundunsor of power circuit i want to know the cundunsor detail like identification of cundunsor that was place at power circuit in my tft hp 1706
admin
January 19, 2010 at 9:06 pm
Hi Ali,
If your LCD Monitor have good output voltages and there the standby light still On, then the LCD Mainboard may have problem.
Jestine
Ivanhoe
February 10, 2010 at 3:31 am
Hi!
I have an HP L1706 17" LCD monitor, when I turn on, there is a strange sound on the back of the LCD, like an airflow sound, if the sound is active the Display works fine, once the sound shuts off the display goes black, when I opened the LCD I hear that the sound is located in one of the Transformers labeled with the following letters (black rectangular component with yellow tape arround):
1J 26060 001
2018M 539021
I was wondering if I can replace this part with another one that do the work, because I am unable to get the same transformer, what do you recommend?...thanks!
admin
February 10, 2010 at 9:30 am
HI Ivan,
It is hard to get the same part. Usually you have to get it from a junk Monitor with the same version and model. Try check if there is any dry joints or not? Try also to gently knock the transformer with the handle of screw driver and if the sound goes off then yo can remove the transformer and dip it into shellac for about 5 minutes and then let it dry for a day and hope the sound will go off.
Jestine
tom
February 26, 2010 at 11:19 am
Hi, I have this same monitor and I have a power issue, but my monitor has no power at all, the led light at the front doesn't even switch on.
When plugged in all I hear is a slight buzzing sound, which I can hear if I put my ear real close to the monitor.
I just wanted to know if this problem was the same as yours (Jestine) or if your monitor had a working green led on at the front (flashing or not).
Also the power board joints are all fine and no damage marks or anything visibly wrong with it.
Will check back soon,
Thanx!
admin
February 26, 2010 at 10:55 pm
HI Tom,
The LCD Monitor was totally no power and what i could suggest in your case is that check all the components in the primary and secondary side of SMPS. It could be bad e-caps, open resistors, leaky diode or transistors or even bad power IC.
Jestine
tom
March 3, 2010 at 9:16 pm
Hi, thanks for your reply and amazing help.
I fixed the problem a few days ago, it was the three caps (1000 micro 10 volt) which were damaged. Thanks to your comments and website (and one of Pierre's comments), I easily fixed the problem.
Thank you for your generous and simply amazing advice!
admin
March 3, 2010 at 9:23 pm
Hi Tom,
You are welcome!
Jestine
PARK DONGWON
March 12, 2010 at 1:01 pm
안녕하세요..
혹시 한국분이신것같아 이렇게 한글로 인사드립니다.
선생님께서 만드신 책을 사고싶은데 어떻게 사야할지 몰라서 이렇게 문으드립니다.
영어를 할지몰라서 이렇게 번역기를 통해서 글을올립니다.
전지금LCD모니터 리페어를 공부하고 있습니다.
하지만 전문지식이 없어 혼자공부하다 선생님의 서적을보고 구매하고싶어서 문의드립니다.
책을살수있는 경로를 알려주시면 감사하겠습니다.
그리고 영어말고 한글로 만든 책이 있으신지요?
정말구매하고 싶습니다.
꼭 연락주싶시요...
010-9289-9659 핸드폰입니다.
전화가 불편하시면 이멜으로 꼭 연락부탁드립니다.
admin
March 13, 2010 at 4:12 am
HI Park,
Sorry, i do not understand your language even with the use of google translation.
Jestine
Jubes
March 17, 2010 at 4:15 am
Hi Jestine,
I have Viewsonic Vx715, when which on the display will stay for 5 secs and then disappear and power light stays green tried to change all 5 caps but problem still persist what else do i have to change? thanks!
admin
March 17, 2010 at 9:15 am
HI Jubes,
It may be the back light problem. But you have to make sure the supply from the SMPS are good and stable.
Jestine
kimi
April 5, 2010 at 11:54 pm
Hi Jestine,
try to find 2761I (Power FET).Do you have it?Stock i mean.Urgently need it.!
pls reply me micrologixz@hotmail.com
thanks
admin
April 6, 2010 at 12:03 am
Hi Kimi,
Sorry i do not sell electronic components. Try email Luca at info@lavinci.it
Jestine
John
April 7, 2010 at 10:08 am
Hi Jestine, this is a great website and your a top individual for sharing your knowledge with us. I have a Dell Monitor E173FPS. The screen is blinking blank and the green light is flashing. I replaced the E capacators and its still blinking and making a slight noise coming from the green board, like a low clicking sound, what is the matter with this? The screen is not damaged but I dont know what the problem with the monitor could be?
John
admin
April 7, 2010 at 8:21 pm
HI John,
You are welcome. In your case, is the output voltages from the SMPS good and stable? Do you get any stable voltage at the vcc pin of the inverter ic?
Jestine
nilesh
April 16, 2010 at 9:16 am
dear sir
sir my hp lcd computer create problem, on screen create small point
but i dont know how they cerate can suggestion about my problem
admin
April 16, 2010 at 8:09 pm
HI Nilesh,
YOU mean some black patches in the screen. If yes it can be repaired and the lcd panel need to be replaced. Sometimes those patches happen due to a constant pressure on the screen.
Jestine
Joey
June 10, 2010 at 6:10 am
Please Help I Have HP L1706 monitor - will not power on - only green light keeps on flashing on power led.
admin
June 13, 2010 at 8:32 am
Hi Joey,
Is the output supply voltages good and stable?
Jestine
Roel R. E. Torres
July 9, 2010 at 5:18 am
My HP L1706 had no power. I opened the LCD and replaced 2 bloated capacitors. When I powered it up the whole screen display blank output but with color and changes continously from red to blue then green and so on... Pls. help!
admin
July 9, 2010 at 5:41 am
Hi Roel,
Most probably the cable connection between the maainboard and the lcd panel has loosen.
jestine
Ong
August 3, 2010 at 12:05 am
Hi,
my Philips 170B7 monitor has no power at all, the led light at the front doesn’t even switch on. I found that there is input voltage to transformer but do not have output voltage. could it possible that the transformer is faulty?
ameh paul
August 3, 2010 at 8:32 am
please help me out. i am working on two Hp L1706 monitors,one has a blown up part which i eant me to recommend a replacement since seems to be customised i.e A27611. the other has a blinking gren light and dosent come on. thank you
ameh paul
August 3, 2010 at 8:49 am
pls,which component can i use to replace A27611 transistor for HP L1706 monitor power unit.i cant get the original part here. thanks
admin
August 3, 2010 at 8:58 am
Hi Ong,
Transformer rarely have problem. I suggest that you check all the components in the primary side and components in the secondary output too. If all check to be okay then direct replace the power IC.
Jestine
admin
August 3, 2010 at 8:58 am
Hi Ameh,
Sorry,no info on this.
Jestine
admin
August 3, 2010 at 9:15 am
Hi Ameh,
When you said blinking greenlight, is the output voltages from the smps good and stable?
Jestine
ameh paul
August 3, 2010 at 10:11 am
yes
admin
August 3, 2010 at 7:22 pm
Hi Ameh,
If all the output voltages good and stable even in the mainboard then the MCU most probably have problem.
Jestine
Jordan
August 16, 2010 at 6:00 pm
I have a syncmaster 203b, does anyone know how to open it so that I can get to the capacitors?
admin
August 17, 2010 at 8:01 am
Hi Jordan,
I have not repair this model before but generally to open all cover is basically the same. Make sure the base and the screws already been removed. Now peel from bottom with a flat metal.Once opened you can peel from the side cover. Please do not use screw driver to peel the cover otherwise it will leave some marking there.
Jestine
Pasan
September 15, 2010 at 10:55 pm
Thank you for your investigative findings. I have been searching high and low for a straight answer, but every other answer on the internet is from idiots who know too much and suggesting we verify VGA output and/or if the RAM is seated properly. I have the exact same monitor that has been taking progressively more and more time to show a display, and yesterday it showed no display at all even after being switched on for 24 hours (checked it this morning, still no display). I finally have proper cause to open it up.
admin
September 16, 2010 at 3:18 am
Hi Pasan,
Once opened up the Monitor, look for bulged e-cap and also dry joints in the inverter area. They are not from the repair line thus do not blame them.
Jestine
Goswami
September 17, 2010 at 1:26 am
i have a samsung syncmaster 920nw in which no display.checked and found 2761I is
totally short and power fuse is blownoff .May i replaced these two or any more.kindly
advise me
admin
September 17, 2010 at 5:39 am
HI Goswami,
I have not repair this model before. As a rule of thumb, you need to check on all the corresponding components before you replace with the new components and retest.
Jestine
Goswami
September 19, 2010 at 5:18 am
please tell me the equivalent of 2761I FET.
admin
September 19, 2010 at 11:20 am
Hi Goswami,
Sorry no info on this part. Yours is the K2761 or the FET inside an IC package?
Jestine
prasanth
October 8, 2010 at 5:30 am
hp l 1706 vertical line problem
admin
October 8, 2010 at 9:47 am
HI Prasanth,
If it is permanent, then replace the LCD panel.
Jestine
Rein
January 16, 2011 at 10:52 am
Hi Jestine.
I'm having issues with my HPL1706 LCD Monitor. Upon turning on my pc, my monitor worked only for a few seconds, and then the entire screen turns out black. I tried to shutdown the monitor and then turn it on again afterwards, however the screen did displayed my desktop but only for a second for it eventually turns out black again. I tried to reboot my pc without unplugging both the cpu and monitor, then the monitor worked perfectly fine.
What do you think is wrong with my monitor? I'm not that familiar with electronics stuff so I really am having trouble with this.
Hope to hear from you. Thanks.
admin
January 17, 2011 at 5:37 am
HI Rein,
This could be caused by bulged filter capacitor, dry joints in the high voltage transformer or even one of the backlight have problem. If you do not know about electricity thing i suggest that you send it to a professional to check it.
Jestine
qaiyumbalhma@gmail.com
February 3, 2011 at 12:44 am
HI I AM PURCHAGE hp l1706(px849a) lcd monitor hp heweltpackard 20555sh249 houston texas manuf-january-2007 spares no-437327-001 my power supply ic(bihind circuit board) and few resistance(serial no-R854,R856,R857,R861) IS balasted by high voltage power supply. there are notlokated the full ic no and resistance power no pleas solve the my problem thanks
uros
February 3, 2011 at 6:43 pm
Hello!
please help me!
I recently got new motherboard for my laptop acer travelmate 2310.
The laptop wasn`t in use for 2 years because original board has died on me. Anyway i replaced the motherboard, fully assembeld the laptop, turned it on and... nothing. There was nothing on the lcd screen. on second look i saw a dim image, thought to my self it must be the ccf lamp because it did work before the motherboard failure. replaced lamp and it is still dimm, so i get new inverter, tried it out-nothing. i tried an external monitor, the picture is great, so it must be the inverter i think.
Got the multimeter, messure the pins and i got these results:
pin 1 0.03V should be 8-20v!! on the other pins the voltage is ok.
Checked the cables and they are all ok.
Inverter number is AS023170147MSS
Can you please tell me what could be wrong that i dont get the requested voltage to inverter?
Thx in advance
admin
February 3, 2011 at 9:45 pm
HI Qai,
Sorry i could not locate the schematic thus i could not find the part number for you.
Jestine
qaiyumbalhma@gmail.com
February 4, 2011 at 12:57 am
HI
JESTIN
I am purchage hp L17069(PX849A) 17-inch LCD Color monitor manufacture-january-2007.
my problem is circuit board bihind power supply smoll ic AND few resistance(serial number-R854,R856,R857,R861) burned.
then not loocated the ic number and resistace(number of power)
plese solve my problem.
thanks.
admin
February 4, 2011 at 11:25 am
HI Qai,
Since i could not locate the schematic thus i could not tell you the exact parts value.
Jestine