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Repaired BenQ FP93V 19″ LCD Monitor
By Jestine Yong on October 14, 2008
The complaint of this BenQ FP93V 19″ LCD Monitor with P/N number 9JL1J72-VWM was no power. As usual have to check primary side first and found that four components have problem. It was a 2 ampere main fuse, .22 Ohm current sense resistor, power FET P7NK80ZFP, and PWM IC 1200AP40. Since i do not have the part number for the power FET, K2645 was used instead. After fixed in all of the components and power “On”, the LCD Monitor came back to life again. The monitor is now under burning in test and should not have any problem with substitution number. In fact i have used that part number to substitute into many different types of LCD Monitors. Here are the photos :
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Ruben
November 18, 2008 at 4:37 pm
i have an AOC LM729 lcd monitor. when i start my computer, it only shows windows desktop for only 2 to 3 seconds then goes black screen, but the power light is still green. when i turn it off and back on, still displays windows desktop for only 2 to 3 seconds then goes black again. pls help... sir jestine . By the way the 2 transistor C5706 in the inverter section are shorted and replace it. when the backlight turn off you can see the display with out the backlight. So i am wondering if this is the case maybe the backlight is busted? or the fault is in the inverter section thanks....
admin
November 19, 2008 at 9:22 pm
Hi Ruben,
There could be two problems, it is either the backlight have problem or the inverter section is at fault because you found two transistor shorted. Trace along the shorted transistor circuit and compare the top and bottom resistance. Any changes in resistance is the clue for you to locate the fault. Hope this helps!
Jestine
moises ardon
December 8, 2008 at 6:12 am
hi im writing from Honduras central america an i have the same problem. i could buy 2 of tree pieces i still looking for 1200ap40 cpam 0548g for a hp lcd monitor 15"...where can i get this piece on the web? and what do you think could be the reason for this unit burn, cause was turn off during the blow.! sorry if you dont get a cleary idea for my bad grammar am learnig english!
admin
December 9, 2008 at 7:55 pm
Hi Moises,
Try email lavinci at info@lavinci.it to check out whether they have this IC or not. When a unit burn, it could be external factor like surge, lightning strike and etc. If it is internal, it could be the components itself that have problem due to quality, heat and etc.
jestine
Paul de Villers
March 3, 2009 at 4:18 am
Hi Jestine,
I have been using a MacMini with a BenQ FP93V for two years with full satisfaction.
All my stuff, including WiFi and sound and printer, are connected to the mains through a UNITEK-France MB 1000 uninterruptible power supply.
All the other components of my installation perfectly work, including the power supply.
What happened yesterday morning is that when I switched the power on, the house main fuse did switch off.
After testing everything, I finally observed the following problem.
When I switch the monitor on the main power supply directly, OR when I switch it through the Unitek power supply while the Unitek is swithched on the house power supply, the house power swithches off.
When I switch the monitor to the Unitek power supply while it is unplugged from the house supply (on batteries), then the monitor and everything else works perfectly !
Thank you for your good advice on that subject.
Paul de Villlers
admin
March 4, 2009 at 11:10 pm
Hi Paul,
Try isolate this problem by bypassing the UPS. If it still trip the house suspect problem either in the cpu or the monitor. If it okay then you know is the UPS fault. You can further isolate this problem by directly connecting your main AC line to the CPU, UPS and the Monitor to see which one causing the house to trip.
Hope this helps!
Jestine
John D. SInipete
April 5, 2009 at 7:42 pm
Good Day Jestine,
can you pls tell me what is the repalcement of the PWM IC 1200AP40 after replacing the shorted power FET P7NK80ZFP, with K2645 no led light, when power “On”, god bless your for your great contribution on this area!.
Tks. John
John D. SInipete
April 6, 2009 at 7:26 pm
John April 6, 2009 725pm Philippnes time
Good Day Mr. Jestine,
On my BENQ 17" LCD MONITOR was the same parts you've mentioned above. I replaced three of those except the 1200AP40 PWM IC cause i can't hardly locate store selling the same kind when i ON the unit still no LED light, there is an excessive heat on 120AP40? pls advice and thank you so much to your website God bless!
John
admin
April 6, 2009 at 8:45 pm
HI John,
So far never come across any replacement (substitution) for the power ic. I guess the best is to get the original part number and check all of the primary side components
Jestine
admin
April 6, 2009 at 10:45 pm
Hi John,
I have the part but shipment to your country would be very expensive.
Jestine
sutris7
June 17, 2009 at 12:09 pm
Hello Mr Justine
I have problem my monitor lg flatron 17"
my lcd no respon went I pust power
and indikator normal
please help me Thanks
admin
June 17, 2009 at 7:51 pm
Hi Sutris,
No response? May i know what is the problem ?No display? display shutdown? and etc?
jestine
Zebron
July 22, 2009 at 2:13 am
Good day sir, i am writing from Nigeria.
i own an BenQ FP93V lcd monitor.When i start my computer, it only shows and allow me to work up to 4 to 5 minutes and after that goes black screen. first i thought my vga cable is not properly plugged but i discover everything is fine. pls help i am in trouble
admin
July 22, 2009 at 7:26 pm
Hi Zebron,
It could be dry joints in the inverter or power board, bad filter cap or even bad backlight.
Jestine
Ross
July 27, 2009 at 7:06 pm
Hi Jestine,
Could you please tell me what wattage the current sense resistor is please
Many Thanks
admin
July 27, 2009 at 9:15 pm
Hi Ross,
It is 1 watt resistor.
Jestine
Ross
July 28, 2009 at 12:25 am
Hi Jestine
Im having real trouble finding a 1 watt 0.22ohm current sense resistor
But i have found a 0.22ohm 0.5watt Safety Resistor.
Is a safety resistor the same as a fusable current sense resistor? and is 0.5 watt ok? Or is it too small?
I can also find a 0.33ohm 2 Watt Fusible Resistor. Would this be better?
So many thanks, this page has been a godsend.
Keep up the good work
admin
July 28, 2009 at 10:23 pm
Hi Ross,
You can try 0.33 ohm 2 watt resistor and if the output voltage is a bit high then i suggest that you get back the same value or parallel the 0.33 Ohm 2 watt resistor. Please don't use 0.5 watt resistor.Hope this helps!
Jestine
cahyono dian
August 10, 2009 at 1:13 pm
switching fet and capacitor 152/2kv before the fet
of ctv philips 21" (I forgot the type)was burnt out.
Can I replace it with FS7UM?
admin
August 10, 2009 at 7:43 pm
Hi Cahyono,
Sorry no info on that Tv I guess you may need to test it out.
Jestine
Lucas Wang
September 28, 2009 at 12:28 am
Would you mind tell me how you determined that 1200AP40 is broken? My monitor got the same problem. After replacing fuse, power FET, and KBP205G, my monitor still could not come back.
admin
September 28, 2009 at 9:35 pm
Hi Lucas,
From experience. Normally whenever the power FET shorted the power IC will gone too.
Jestine
chr10000
October 23, 2009 at 6:14 pm
hello, how do you tell how to replace power fet with alternate. what are good methods for testing them.
admin
October 23, 2009 at 8:50 pm
Hi Cr1000,
All these information can be found in my ebook Testing electronic components.
Jestine
John McGivern
October 31, 2009 at 12:10 am
Hi Justine, I have been reading quite a lot of your replies and your own website.I have never tackled electronic problems before, unless really obvious.My problem at the moment is HP 1907W LCD MONITOR just out of warrenty. Power supply problem I think replaced suspect caps electrolytics but there is a smd resistor looks like 103 or 105.
Tried everywhere for a circuit or parts list for monitor but unsuccessful.Could you possibly advise of any website I could acquire a circuit/schematic or BOM LIST.
Best regards, John.
PS I downloaded your power supply info from your site trying to get my head around it.
I went to RGIT AT ABERDEEN for survival training.
Small world. Cheers.
admin
October 31, 2009 at 4:50 pm
Hi John,
Any output voltages measured from the SMPS? If zero output then concentrate on the primary side components. Sorry, i do not have this schematic diagram. SMD resistor rarely have problem. A 103 code is a 10K ohm value and 105 is 1 meg ohm. Nice to know that you have attended the course at RG University.
Have a good day!
Jestine
gibson
November 2, 2009 at 12:00 am
my AXIZ LCD MONITOR just stoped working nothing is coming on, i openned & cheked the power suply i only removed the k2645 transister but i dont know how chek this transister.& if it not ok what other number is equivalent to this.please help me
admin
November 2, 2009 at 7:59 pm
HI Gibson,
You can try K1507.
Jestine
srba
November 7, 2009 at 7:43 am
Monitor is BENQ Q9T4.Voltages on secondary exist(5V;3.3V and 15V for invertor).No LED on front,no power.How this lcd get start.
admin
November 8, 2009 at 3:46 pm
Hi Srba,
If all the voltages present then suspect a bad mainboard.
Jestine
srba
November 8, 2009 at 9:37 pm
Is that board with processor?
Does LCD monitor work without computer(or any signal on vga conn.)
Thanks for answer and advice.
admin
November 9, 2009 at 10:30 am
Hi Srba,
Yes the processor board. All LCD Monitors need a signal in order to function.
Jestine
Gibson Chinyoni
November 27, 2009 at 7:13 pm
Hi jestine,
i managed to replace k2645 with the new one but still nothing.
how do i check if the power supply is ok. if the mainboard is gone,is it posible to find one for my 19" AXIZ LCD MONITOR
admin
November 28, 2009 at 5:09 pm
HI Gibson,
Sorry no info about that mainboard. In order to check if the power supply is okay or not you must check that there are good output voltages present at the secondary output side. Place your meter black probe to the cold ground and the red probe to the cathode side of the diode or schottky diode and power On. If no voltage then you must check all components in the primary side.
Jestine
nelson paz
December 5, 2009 at 8:27 am
you are just amazing mr.yong.but how do i know when the pwm ic is not working like it should . see i have a dell m170eg01 but this one powers up give me the video for just a second then back off, and so for. i have checked diodes transistor resistor , until know i will replace all the condensor. i will letl you know, how does it come out
the i will be in the need of your precious help mr. yong. thanks you so much sir.
admin
December 7, 2009 at 9:43 pm
HI Nelson,
If the SMPS have good output voltages then check the backlight.
Jestine
bob
January 18, 2010 at 10:58 pm
i have benq fp91g+ [model q974] will only power on with both power and enter buttons depressed at the same time screen then works but no screen buttons will work have you seen a similar fault before
admin
January 19, 2010 at 1:11 am
Hi Bob,
Do you mean that you press two buttons simultaneously then only it will work other wise there will be no power?
Jestine
bob
January 19, 2010 at 9:11 pm
jestine
yes press two buttons simultaneously power and enter then it will switch on
lcd works fine osd does not
cannot use any buttons cannot switch off
bob
admin
January 20, 2010 at 5:48 am
HI Bob,
In that case chances is high the EEPROM ic data corrupted or you have a bad Mainboard. Most probably bad MCU.
Jestine
Suminona
February 12, 2010 at 3:30 am
Same Benq Q94T , fuse and resistor is ok .. so monitor turns on if u look closely u can see the Benq logo (so the invertor part is malfunctioning) when it starts ... The capacitors are ok from the board .. basicaly ... i need to replace 1200Ap40 and P7... (k2645) part ? tks for help
admin
February 12, 2010 at 6:21 am
Hi Suminona,
Since you already could see the dim logo, then it is not the power side problem. So please do not change the power IC 1200AP40 AND THE POWER FET.
Make sure the inverter IC have supply voltage input and the transistors are good.
Jestine
Suminona
February 13, 2010 at 3:10 am
Actualy i dont have 12-16 volts at pin 9 for TL1451 , and q805 and q812 are ok ... so i suspect the TL1451 part to be fried . Unfortunately im my area i cant get that part, can u give me an alternative for that ? or what to check ?
Sorry for this but i have only basic knowhow ,
Thanks a lot
admin
February 13, 2010 at 10:26 am
Hi Suminona,
Try remove the Tl1451 IC and see if the voltage comes back or not. If yes then i guess you may have a shorted IC. By the way, there is no alternative to this IC.
Jestine
zoltan
February 22, 2010 at 1:35 pm
hi Jestine, my power supply has a varistor? #TR601 that has exploded, so I can't determine the part #. It's located by the largest capacitor. Would you please tell me what it is? Thank you very much.
zoltan
February 22, 2010 at 2:41 pm
Also, I'm in California, do you have the IC so that I could buy it from you?
admin
February 23, 2010 at 6:14 am
HI Zoltan,
If you confirmed that it is a varistor then you can buy a 175 Vac varistor (if your country use 110vac) or 275vac if your country is using 240vac supply.
Jestine
admin
February 23, 2010 at 6:16 am
HI Zoltan,
Sorry we do not sell parts anymore but you can email luca at info@lavinci.it. You may email him to check for other components too.
Jestine
Robert
March 31, 2010 at 4:05 pm
Hey,
I'm trying to get a HP L1940 with a BenQ 48.L1G02.A00 board back to life.
It has a dead 2amp main fuse(TR5), 0R22 Resistor, a mosfet K3673 and the 1200AP40 PWM controller IC. I replaced the fuse and resitor already but im still looking for a replacement for the mosfet and the IC in Europe. Got any tips?
Thanks
admin
April 1, 2010 at 8:07 am
HI Robert,
Try email Luca at info(at)lavinci.it to check if he has the parts or not.
Jestine