Having problems with your HP Pavilion F1903 19" Flat Panel LCD Monitor ?

Testing C5707 Transistors on Benq Inverter Board

\015 Hello everyone,\015\012\015\012\015\012I have a faulty HP 1940 with a Benq\015\01248.LIG02.A01 inverter board. It has the fault where it the screen\015\012goes black after a few seconds, after putting a flash light to it I\015\012could see that the image was still there. i Opened it up and\015\012inspected the inverter board I could not see any faulty caps and the\015\012soldering looks good to me (I'm a novice) so after reading through\015\012the posts here I decided to pull the four C5707 transistors off the\015\012board and test them with my DMM, as I have read here that these\015\012transistors are a common fault with this board. Because I have\015\012little experience testing transistors I was hoping for some\015\012conformation from the experts (you)\015\012\015\012\015\012\015\012I pulled 4 transistors off the board\015\012and kept them separated in pairs as I'm told the fail in pairs.\015\012\015\012\015\012The first pair gave me the following\015\012results (all tested with the diode function on my DMM)\015\012\015\012\015\012Transistor 1 (first pair)\015\012\015\012\015\012B-E .575 v\015\012B-C .575v\015\012C-E Open\015\012E-C Open\015\012\015\012\015\012Transistor 2 (first pair)\015\012Same as above\015\012\015\012\015\012Transistor 3 (second pair)\015\012B-E 0.00v (it did not read 0L )\015\012B-C .349v\015\012C-E .349v\015\012E-C .360v\015\012\015\012\015\012Transistor 4 (second pair)\015\012B-E 0.00v (it did not read 0L )\015\012B-C .444v\015\012C-E .478v\015\012E-C OPEN\015\012\015\012\015\012it seems to me that the second pair is\015\012faulty I was wondering if anyone can confirm this? I have found a\015\012place on ebay where I can order some new C5707s. Also As a precaution\015\012I have touched up the soldering on all the transformers in case this\015\012was the cause of the fault. Anything else I should check?\015\012\015\012\015\012Thanks heaps for all the great tips I\015\012found here I would never have tried this without the advice I have\015\012found on this site.\015\012\015\012\015\012Mike\015

Answers :

Repair Help & Product Troubleshooting for HP Pavilion F1903 19" Flat Panel LCD Monitor

Tips for a great answer:

- Provide details, support with references or personal experience .
- If you need clarification, ask it in the comment box .
- It's 100% free, no registration required.

Suggested Questions/Answers :

Testing C5707 Transistors on Benq Inverter Board

... HP Pavilion F1903 19" Flat Panel LCD Monitor

Benq fp737 17

How old are the monitors?\015\012Normally backlights last at least 30,000hrs of working.\015\012Normally problems on Inverter board transistors near yellow inverter transformers.\015\012Samir ... BenQ FP731 17" LCD Monitor

I have a dell inspiron 9300 with win xp pro for an os, my lcd screen is broke, so i took it off completly. now i am trying to hook up an benq fp567s monitor through the vga output. it will get me as far as desktop screen just after boot up. & most of the time it goes in to sleep mode before start up is complete. the screen suddenly displays "no signal" ?

Many people have noted two primary failures with this monitor. i have a couple time-saving troubleshooting tips, which actually apply to mostly all electronic devices. first, of course, bulging electrolytics [capacitors] should be considered suspect. ... BenQ FP567s 15" LCD Monitor

Found them ah found them....so if i change these 4 will it make the screen work again?? do i test them as a normal transistor test ? can i test them in situ on board or remove to test ? many thanks for your help viziks....andy

If you are referring to the C5707 inverter driver transistors, you can test them in circuit with an ohmmeter. Usually one pair will show shorted although only one may be actually shorted. Normal procedure is to replace the pair that shows in circuit ... BenQ FP737S-D 17" LCD Monitor

Gone from blinkid led to lights out.

You really need to replace all 4 and also the 2 FU9024 chips and examine all the solder in the inverter area. Also if you have the 2 lamp connector board with a chungwa LCD panel them your lower lamp is probably also bad. Check out ... Dell E172FP 17" LCD Flat Panel Monitor

BenQ FP72G 17" LCD Monitor NO DISPLAY but when i shine a torch on the screen, it shows the display. Does anyone know exactly which compoent i need to replace on the Inverter board ? All transistors seems to be short circuited ?

The parts list..Here we go again =)\015\012\015\0124x 2SC5705 (can also be 706 as well)\015\012Bridge capacitors (near the transistors) - Replace\015\012Transformers (can be eithe ... BenQ FP72G+ 17" LCD Monitor

Benq 17"Lcd monitor fault

Resolder the power transistors on inverter board and also check them.If display is not there at all some of this 4 transistors C5707 should be defective.Check associated fuse and Fet which drives the transistor.\015\012\015\012Also check ... BenQ FP737S-D 17" LCD Monitor

BenQ FP51g LCD monitor

Dear Friend:\015\012 There is a Switch transistor to power on -off the hi voltaje for lights. Check 15V from power source go to this transistor colector, Using soldering Iron, make a juntion between colector and emiter, to short 15V to Hi volt ... Proview PL713S 17" Flat Panel LCD Monitor

Back light goes out after start up - Dell E172FP 17" LCD Flat Panel Monitor

You have BenQ syndrome.\015\012Sounds strange I know, but the power supply in your monitor is a BenQ manufactured part.\015\012The problem is in the inverter section of the power/inverter board.\015\012There are 4 small transistors ... Dell E172FP 17" LCD Flat Panel Monitor

Monitor Dell e152Fp Power on - (black screen)- can see desktop when using a flashlight. I have taken the monitor apart and there are no buldging or leaking caps on the inverter board or other board. I also have tried to increase contrast and brightness and it did not fix the issue. Should I test the other parts in the circuit? How do I do that?

You need to chek for shorts between Emitter and Collector of the transistors C5707 in the inverter circuits, and also check the fuse PF751 for less than one Ohm resistance. Here are the pictures: ... Dell E152FP 15" Flat Panel LCD Monitor

Benq inverter board schemtic

Post me a picture of the board and I might be able to Help.Normally transistors 2Sc5707 are defective.\015\012Samir.\015\[email protected] ... BenQ FP71G 17" LCD Monitor

Hewlett-Packard vs17 half fixed, what to do next?

Hello,I have also seen this type of problem. Have you checked the large caps on the inverter board, no just the power supply board? Many LCD monitors have 2 caps on the inverter and I have had to replace them from time to time. The next t ... HP vs17c 17" LCD Monitor

Monitor powers on for approx 8 secs then standby.Series of vertical stripes on panel but no image.Guessing the lcd is at fault?

When I applied the solution below, I go stripes when poorly reconnecting the logic board to the plate, and the plate ability to do it job can be effect by bits going on the inverter, wavely screen output etc. The lcd is an assembly kit inside have a ... iiyama ProLite E434S 17" LCD Monitor

19" Proview 900p lcd monitor backlight

Change the capacitors (all but maybe the main should be done- if you\015\012change just bad ones now, the others will take the heat and go soon).\015\012They do not have to be bulged or leaking to be bad.\015\012Then if that doesn't help, shoot ... Gateway FPD2275W LCD Monitor

BenQ FP767 17" LCD Monitor Problem

IT seems you are not technically trained in electronics.In this case it's difficult to explain via this board,Best you find someone to fix it for you,you can try contacting Benq Support locally.\015\012Sorry for not being able to help.\01 ... BenQ FP767 17" LCD Monitor

Problem for BenQ FP767 Power light does come on, image is there if a light is shined on the screen, i have swapped the 4 2sc5707 transistors as suggested in other posts. Still the same problem, further testing shows no power in the entire area around the transistors (tested across the majority of surrounding connections). Could there be a further problem and is it possible to obtain a board diagram so i can try and track the point of power loss?

Change the board ... BenQ FP767 17" LCD Monitor

Monitor on but no/very feint display

Sorry for the late reply, I was sent away for 2 weeks in the middle of nowhere.\015\012\015\012Anyway to the problem at hand..\015\012\015\012The transistors are easy to check. They have 3 legs so think of them as 1, 2 (middle ... BenQ FP767 17" LCD Monitor

BenQ FP731 17" Inverter transistors

T751,752,753,753 are the transformers to be resoldered ,and resolder Transistors Q759,60,39,40,43,51.\015\012Please check them with a multimeter if you are adept .\015\012Please rate the solution and provide feedback.\015\012Samir ... BenQ FP731 17" LCD Monitor

Mag Innovison LT917S LCD Monitor

After looking at the description of the pin outs on the BIT3193 and following signals to/from that chip I discovered I had burned up one of the FETS that I had installed. With the FETS replaced for the second time the monitor works fine now. HEY!! ... Gateway FPD2275W LCD Monitor

BenQ FP767 17" Power but no display?

Different faults here.\015\012First fault is no power, it is bad capacitors on the power board.\015\012\015\012Second & third faults are the inverters. (power but no image visible, but feint if you shine a light into the screen) ... BenQ FP767 17" LCD Monitor

Clarity bobcat monitor, no picture black screen

This is a generic symptom that could happen to any LCD\015\012monitor.\015\012\015\012\015\012The following is a generic answer applicable to most.\015\012\015\012\015\012\015\012\015\012\015\012Two possible causes are bad capacitor ... Computer Monitors

Powers on ,no picture - HP Pavilion F1903 19" Flat Panel LCD Monitor

I will assume that you already try it on another PC and still get the same symptom. You will have to open it up and look for bad solder connection in the backlight inverter board, burnt parts, shorted transistors, bad inverter transformers, bad lamps ... HP Pavilion F1903 19" Flat Panel LCD Monitor

No backlight in Benq fp767-12 I have replaced all c5707 on inverter board and fu9024n and few capacitors but it still does not work

If you can expose it, examine the ends of the fluorescent tube itself; if there are prominent black rings at the end, the tube is toast.\015\012These cost much less to replace and live only about 4-5,000 hours, much shorter than the inverter board ... BenQ FP767-12 17" LCD Monitor

Monitor will not work

Your model number indicates the LCD is made by BenQ. This model is known for poor solder connection causing the inverter driver transistors to short, resulting in immediate shutdown if the inverter circuit. Disassembly and testing the transistors is ... Computer Monitors

BenQ FP767 17" LCD Monitor Problem - Power LED Blinks

Look for small power transistors 2SC5707 near yellow invertor transformers which go to backlight connectors.\015\012But if problem is blinking power LED powersupply capacitors maybe an issue,check visualy and/or replacement.\015\012Also f ... BenQ FP767 17" LCD Monitor
  • Start your question with What, Why, How, When, etc. and end with a "?"
  • Be clear and specific
  • Use proper spelling and grammar
all rights reserved to the respective owners || www.electronic-servicing.com || Terms of Use || Contact || Privacy Policy
Load time: 0.2545 seconds