Dell E151Fpb How To Restore LCD Monitor - No Display Problem Manual Guide
Dell E151fpb LCD monitor came in with the complaint of no power however upon carefully have a look at the LCD you could possibly see a very mild (blur) white flashes throughout the display screen and the ability LED will not be lit. Removing the quilt was a bit straightforward compared to different models. As ordinary each time the mainboard and energy board have been exposed, I would search for any bulged capacitor, darkened space, a loosen connector and etc. Nevertheless this monitor boards appears perfectly okay. The next step was to separate the ability/inverter board with the principle board. Power was utilized to the ability board and I might hear a soft 'chip-chip' sound. Once I measure the 12 volts line with a digital multimeter, the readout was about 7- eight volts which was very unusual. In reality this is excellent news to us because we all know what the subsequent step that we must always make.
Now we could use a 12 volt automobile brake light bulb to test at which section that is inflicting the low voltage output problem. If the LCD monitor designed to run on 18 or 24 volts then you might use a light bulb from the large trailer. A defective part in either main or secondary aspect might cause low output voltage. Removing the fuse as shown within the photograph and connect the bulb between the availability line and the cold ground may inform which part is giving problem. You might use this technique but first you should verify that the secondary filter capacitors, TL431 adjustable precision shunt regulator ic, optoisolators and parts surrounding the optoisolator is working earlier than you proceed to use the sunshine bulb.
When the facility is on the sunshine bulb nonetheless do not lit and the sound nonetheless could possibly be heard. This indicates that the first side is having drawback and we will go away the inverter/high voltage area and totally focus to find the faults in the major section.
That is the time to essentially test your basic electronics skill since you now know at which area the fault is and also you just have to make use of your skills to locate the precise bad component. There weren't a lot components in the major facet, and you may easily test all of them in less than 20 minutes. After checking all of the components I used to be surprised that all of them examined okay. Main winding of change mode energy transformer rings eight bars which signifies good and even the uc3842b PWM power IC replaced the ability still won't work! It was fairly difficult to troubleshoot this sort of downside where you are hundred p.c certain that the first aspect is giving drawback yet you possibly can not find out the culprit.
Since I had checked all the elements and couldn't find the fault, the one way that I could do is to direct change the semiconductor units such because the diodes, scr, fet, and transistors. From experienced I do encountered semiconductor parts breakdown when beneath full operating voltage. One by one of many semiconductor elements I replaced and energy on each time I had changed it to see if the bulb light up or not. Guess what, you wouldn't believe what have I just discovered-a defective 2N7000 fet! The moments I have replaced this fet and power on, the bulb instantly gentle up. I could not consider it was this defective fet that causes all the output voltages to drop! I was so joyful that I ultimately solved the problem and who knows this might be a typical fault for all DELL E151Fpb LCD monitor- so please take notice to all LCD monitor repairer.
I began to verify again the faulty 2N7000 fet with my analog meter and peak digital atlas part analyzer and the end result is still the same-tested good! Identical to flyback transformer, the very best testing tools to test Fet and different parts is actually the gear itself because it runs on full working voltage, frequency, sign and etc. What you've gotten just learned from right here was that if all of the suspected elements tested good, the one approach to reveal the reality is to direct change the parts. Hope you take pleasure in this article and more good articles to return on a regular basis! Wishing you all the most effective and completely happy repairing!
Dell E151Fpb How To Restore LCD Monitor - No Display Problem Manual Guide
Dell E151fpb LCD monitor came in with the complaint of no power however upon carefully have a look at the LCD you could possibly see a very mild (blur) white flashes throughout the display screen and the ability LED will not be lit. Removing the quilt was a bit straightforward compared to different models. As ordinary each time the mainboard and energy board have been exposed, I would search for any bulged capacitor, darkened space, a loosen connector and etc. Nevertheless this monitor boards appears perfectly okay. The next step was to separate the ability/inverter board with the principle board. Power was utilized to the ability board and I might hear a soft 'chip-chip' sound. Once I measure the 12 volts line with a digital multimeter, the readout was about 7- eight volts which was very unusual. In reality this is excellent news to us because we all know what the subsequent step that we must always make.
Now we could use a 12 volt automobile brake light bulb to test at which section that is inflicting the low voltage output problem. If the LCD monitor designed to run on 18 or 24 volts then you might use a light bulb from the large trailer. A defective part in either main or secondary aspect might cause low output voltage. Removing the fuse as shown within the photograph and connect the bulb between the availability line and the cold ground may inform which part is giving problem. You might use this technique but first you should verify that the secondary filter capacitors, TL431 adjustable precision shunt regulator ic, optoisolators and parts surrounding the optoisolator is working earlier than you proceed to use the sunshine bulb.
When the facility is on the sunshine bulb nonetheless do not lit and the sound nonetheless could possibly be heard. This indicates that the first side is having drawback and we will go away the inverter/high voltage area and totally focus to find the faults in the major section.
That is the time to essentially test your basic electronics skill since you now know at which area the fault is and also you just have to make use of your skills to locate the precise bad component. There weren't a lot components in the major facet, and you may easily test all of them in less than 20 minutes. After checking all of the components I used to be surprised that all of them examined okay. Main winding of change mode energy transformer rings eight bars which signifies good and even the uc3842b PWM power IC replaced the ability still won't work! It was fairly difficult to troubleshoot this sort of downside where you are hundred p.c certain that the first aspect is giving drawback yet you possibly can not find out the culprit.
Since I had checked all the elements and couldn't find the fault, the one way that I could do is to direct change the semiconductor units such because the diodes, scr, fet, and transistors. From experienced I do encountered semiconductor parts breakdown when beneath full operating voltage. One by one of many semiconductor elements I replaced and energy on each time I had changed it to see if the bulb light up or not. Guess what, you wouldn't believe what have I just discovered-a defective 2N7000 fet! The moments I have replaced this fet and power on, the bulb instantly gentle up. I could not consider it was this defective fet that causes all the output voltages to drop! I was so joyful that I ultimately solved the problem and who knows this might be a typical fault for all DELL E151Fpb LCD monitor- so please take notice to all LCD monitor repairer.
I began to verify again the faulty 2N7000 fet with my analog meter and peak digital atlas part analyzer and the end result is still the same-tested good! Identical to flyback transformer, the very best testing tools to test Fet and different parts is actually the gear itself because it runs on full working voltage, frequency, sign and etc. What you've gotten just learned from right here was that if all of the suspected elements tested good, the one approach to reveal the reality is to direct change the parts. Hope you take pleasure in this article and more good articles to return on a regular basis! Wishing you all the most effective and completely happy repairing!
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Although the English in this was unusual and even humorous, it was enough to assist me in my own troubleshooting of my E151FPb monitor with similar problems. The FET in question is marked Q604 and is the small D-shaped black transistor package near the CN701 14-pin connector. It's the only with that's marked with D...G...S... pinouts, which is helpful. Can't say whether or not this will fix my monitor but I see no bulging electrolytic capacitors so I'm going to take a chance that mine also has the same problem.
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