LCD Monitor Problems - Easy Way To Check up It for Repair
As we speak's article talks about repairing the CMV 19" LCD Monitor problems model CM-922D. The complain was no power as what the client informed me. This energy provide was not built into the circuit thus it need an exterior power adapter to power it up. The enter to the LCD Monitor is 19V with 3.1 Amp from the adapter. For the reason that complain was no power, we have now to try it out to verify if the ability adapter is at fault or the LCD Monitor.
The ac provide was plugged in to the ability adapter and I might see the power LED was lighted up. Checking the output voltage of the power adapter I acquired about 19 volts which is good. Despite the fact that the LED has lit and correct output voltage, this does not imply that the facility adapter can preserve when there is a load (the LCD Monitor) related to it. I as soon as got here throughout a Compaq 17" LCD Monitor which have a exact output voltage from the power adapter however when connected to the Monitor, the display appeared for a fraction of a second before shutting down. Normally in this case, your skilled would let you know that it could possibly be the inverter circuit are faulty or the lamps have problem. You'd be stunned that the actual reason for the shutdown was because of the power adapter. It will possibly't maintain the output voltage when there's a load on it.
This kind of fault was usually because of a nasty filter capacitors located at the output of the secondary circuit. If you have ESR meter, you'll be able to really locate the faulty electrolytic capacitors fast. If you do not have the meter, just direct exchange the caps. As talked about in my earlier restore articles, to substantiate if the facility adapter is really working or not you want a lightweight bulb to behave as a load. Ensure that the ability LED light would not blink each time the sunshine bulb is connected. Even when it blinks one time, this proves that the regulation shouldn't be good and need to be check entirely. Within the above china made LCD Monitor, the ability adapter work perfectly positive!
Since I've already confirmed that the ability adapter is nice, my focus now was on the LCD boards. Eradicating this cowl was very simple and you'll easily entry to the board when the metal casing was removed. The very first thing that I checked was the SMD fuse positioned in the principle board. If the fuse opens then there could be no provide to the ADC/SCALAR and the CPU IC thus the facility LED would not light! Checking this SMD fuse was fairly easy as the strategy of checking it's the same like a traditional fuse. Use both an analog or a digital meter set to ohms vary or continuity check. You can examine the fuse while it's still in circuit. Yes, the fuse was found to be open circuit.
Now there is one question that must be answered by us. What makes the fuse to go open circuit? Properly from what we have identified about digital repair, there are three prospects as why a fuse opens circuit. First, the fuse can turn out to be open circuit as a consequence of its lifespan. Some fuses can last for a few years whereas some only couple of years. In other phrases, the life span of a fuse depends on the qualities of the supplies used. Secondly, the external factor resembling a surge inflicting the fuse to open circuit as a way to shield the main board. Thirdly, the main board itself have drawback (comparable to a shorted IC's and different digital parts) that precipitated the fuse to open circuit.
If the LCD Monitor problems falls within the first and the second classes then changing solely the fuse will definitely solve the problem. Nevertheless, for this LCD Monitor, changing only the fuse did not work at all and the fuse open circuit again. You might have solely two choices to solve this sort of problem. First you need to use an exterior regulated energy provide as explained in my previous restore articles and join the detrimental output of the ability supply to floor and the optimistic to the fuse (the road that leads to other circuitry) in an effort to detect the brief circuit. Slowly differ the output voltage and monitor the present drawn. As soon as the current drawn a few amp or two, now place your finger to any digital elements in the main board. In case you discovered any elements that get extremely popular then that's the cause of the quick circuit.
In this article, I'm going to do it differently to detect the brief circuit. Are you ready? Now instead of changing the fuse with the precise rating which is 3 amperes, I replaced it with a 5 amperes fuse. The purpose for me to put the 5 amp fuse as a substitute of the 3 amp fuse was because "if the fuse doesn't blow then the element which have brief circuit would blow". Do you get the concept? Three issues can happen whenever you use this approach to power out the culprit. First the power adapter may shut down attributable to heavy current draw from the primary board. Second, the quick circuit electronic components (both be a IC, diode, capacitors, transistor and and many others) will get hot and you can quickly locate it simply by touching them. Bear in mind do not on it for too long otherwise if the shorted elements get too hot it's going to go open circuit and now you'll have a tough time to locate the fault. Third, it's possible you'll hear a pop sound and spark from the shorted component. Trace from the place the spark came from and you may simply establish the location and sometimes to the actual element that generate the spark.
For the above LCD Monitor, I really noticed a small spark on the prime a part of the primary board once the power input jack was connected. It prompted me to the exact location and when I examine the SMD ceramic capacitor (that generated the spark beneath it) with analog meter set to X 10 Ok ohm vary; it actually developed a slight quick circuit. Changing solely the fuse and the SMD ceramic capacitor solved the no energy downside in this 19" LCD Monitor. This Monitor uses the inverter IC (OZ960G), A1084-25CM (2.5 volts voltage regulator), AMC1117-3.three (3.three volts voltage regulator), ADC IC (MST8136B) and CPU IC (MYSON MTV312MV64).
Conclusion-There are all the time choices as to which methods that you need to use to detect the short circuit. If you prefer the latter one, then I suggest you to take some photo shots first before something actually burnt out past description. With the images, a minimum of it offers you some hints of what the components is perhaps and even the half numbers. Properly, there's at all times an attention-grabbing technique to solve digital problems and this is likely one of the purpose that I like digital repair a lot as a result of you'll be able to all the time act as a detective to find out the wrongdoer-real satisfaction! Oh! By the way, you should use the above technique to every other electronic tools and it's not limited solely to issues repair. Have an awesome hunt my pal!
LCD Monitor Problems - Easy Way To Check up It for Repair
As we speak's article talks about repairing the CMV 19" LCD Monitor problems model CM-922D. The complain was no power as what the client informed me. This energy provide was not built into the circuit thus it need an exterior power adapter to power it up. The enter to the LCD Monitor is 19V with 3.1 Amp from the adapter. For the reason that complain was no power, we have now to try it out to verify if the ability adapter is at fault or the LCD Monitor.
The ac provide was plugged in to the ability adapter and I might see the power LED was lighted up. Checking the output voltage of the power adapter I acquired about 19 volts which is good. Despite the fact that the LED has lit and correct output voltage, this does not imply that the facility adapter can preserve when there is a load (the LCD Monitor) related to it. I as soon as got here throughout a Compaq 17" LCD Monitor which have a exact output voltage from the power adapter however when connected to the Monitor, the display appeared for a fraction of a second before shutting down. Normally in this case, your skilled would let you know that it could possibly be the inverter circuit are faulty or the lamps have problem. You'd be stunned that the actual reason for the shutdown was because of the power adapter. It will possibly't maintain the output voltage when there's a load on it.
This kind of fault was usually because of a nasty filter capacitors located at the output of the secondary circuit. If you have ESR meter, you'll be able to really locate the faulty electrolytic capacitors fast. If you do not have the meter, just direct exchange the caps. As talked about in my earlier restore articles, to substantiate if the facility adapter is really working or not you want a lightweight bulb to behave as a load. Ensure that the ability LED light would not blink each time the sunshine bulb is connected. Even when it blinks one time, this proves that the regulation shouldn't be good and need to be check entirely. Within the above china made LCD Monitor, the ability adapter work perfectly positive!
Since I've already confirmed that the ability adapter is nice, my focus now was on the LCD boards. Eradicating this cowl was very simple and you'll easily entry to the board when the metal casing was removed. The very first thing that I checked was the SMD fuse positioned in the principle board. If the fuse opens then there could be no provide to the ADC/SCALAR and the CPU IC thus the facility LED would not light! Checking this SMD fuse was fairly easy as the strategy of checking it's the same like a traditional fuse. Use both an analog or a digital meter set to ohms vary or continuity check. You can examine the fuse while it's still in circuit. Yes, the fuse was found to be open circuit.
Now there is one question that must be answered by us. What makes the fuse to go open circuit? Properly from what we have identified about digital repair, there are three prospects as why a fuse opens circuit. First, the fuse can turn out to be open circuit as a consequence of its lifespan. Some fuses can last for a few years whereas some only couple of years. In other phrases, the life span of a fuse depends on the qualities of the supplies used. Secondly, the external factor resembling a surge inflicting the fuse to open circuit as a way to shield the main board. Thirdly, the main board itself have drawback (comparable to a shorted IC's and different digital parts) that precipitated the fuse to open circuit.
If the LCD Monitor problems falls within the first and the second classes then changing solely the fuse will definitely solve the problem. Nevertheless, for this LCD Monitor, changing only the fuse did not work at all and the fuse open circuit again. You might have solely two choices to solve this sort of problem. First you need to use an exterior regulated energy provide as explained in my previous restore articles and join the detrimental output of the ability supply to floor and the optimistic to the fuse (the road that leads to other circuitry) in an effort to detect the brief circuit. Slowly differ the output voltage and monitor the present drawn. As soon as the current drawn a few amp or two, now place your finger to any digital elements in the main board. In case you discovered any elements that get extremely popular then that's the cause of the quick circuit.
In this article, I'm going to do it differently to detect the brief circuit. Are you ready? Now instead of changing the fuse with the precise rating which is 3 amperes, I replaced it with a 5 amperes fuse. The purpose for me to put the 5 amp fuse as a substitute of the 3 amp fuse was because "if the fuse doesn't blow then the element which have brief circuit would blow". Do you get the concept? Three issues can happen whenever you use this approach to power out the culprit. First the power adapter may shut down attributable to heavy current draw from the primary board. Second, the quick circuit electronic components (both be a IC, diode, capacitors, transistor and and many others) will get hot and you can quickly locate it simply by touching them. Bear in mind do not on it for too long otherwise if the shorted elements get too hot it's going to go open circuit and now you'll have a tough time to locate the fault. Third, it's possible you'll hear a pop sound and spark from the shorted component. Trace from the place the spark came from and you may simply establish the location and sometimes to the actual element that generate the spark.
For the above LCD Monitor, I really noticed a small spark on the prime a part of the primary board once the power input jack was connected. It prompted me to the exact location and when I examine the SMD ceramic capacitor (that generated the spark beneath it) with analog meter set to X 10 Ok ohm vary; it actually developed a slight quick circuit. Changing solely the fuse and the SMD ceramic capacitor solved the no energy downside in this 19" LCD Monitor. This Monitor uses the inverter IC (OZ960G), A1084-25CM (2.5 volts voltage regulator), AMC1117-3.three (3.three volts voltage regulator), ADC IC (MST8136B) and CPU IC (MYSON MTV312MV64).
Conclusion-There are all the time choices as to which methods that you need to use to detect the short circuit. If you prefer the latter one, then I suggest you to take some photo shots first before something actually burnt out past description. With the images, a minimum of it offers you some hints of what the components is perhaps and even the half numbers. Properly, there's at all times an attention-grabbing technique to solve digital problems and this is likely one of the purpose that I like digital repair a lot as a result of you'll be able to all the time act as a detective to find out the wrongdoer-real satisfaction! Oh! By the way, you should use the above technique to every other electronic tools and it's not limited solely to issues repair. Have an awesome hunt my pal!
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