Understand some knowledge related to LED screen maintenance
LED display is widely used, we inevitably encounter some unexpected situations in the process of use, resulting in the LED display function is affected.
Electronic devices are not permanently maintain perfect performance of the goods, understand some simple LED screen repair related knowledge, can help us understand in the encounter fault how to solve it.
Troubleshooting before LED screen repair
Visual inspection of the screen
In the event of a LED display malfunction, we can follow a simple to complex troubleshooting sequence.
The first step is of course to find the problem through direct observation, try to find the fault point from the appearance of the display above, determine the cause of the failure, think about the LED screen repair method.
Bad spots
If there are some pixels on the LED display that do not light up, or the color of a single bead does not change and stays at a certain color, this situation is usually called a bad spot.
Uneven color
The appearance of uneven color of LED screen, a certain piece of dark color, a certain piece of light color, may be caused by the performance of the LED beads used is too poor.
Uneven brightness
If the brightness of the LED display is uneven, it may be caused by uneven current distribution, and you need to check the connected power cables.
Check all cable connections
Check all the cables of the LED display, whether it is current transmission or signal transmission, to see whether the cable interface is loose, or whether the cables are correctly connected to each other, any cable is not properly connected may affect the subsequent display effect.
Power cycle
Power off the malfunctioning LED display and wait for a few minutes, then reconnect the power supply to see if the LED screen display picture is any better.
Try different inputs
Replace the content source of the LED display, observe whether the fault still exists after the replacement of the content source, if the display is still incorrect then try to replace the cable, through the replacement of both the subsequent display results obtained by comparing, to determine the cause of the fault is in the content source or in the LED display itself.
Adjustment of display settings
Adjust the LED screen playback parameters and content source video parameters to achieve consistency, parameter mismatch may also lead to display errors or poor display.
Check for physical damage
In addition to the obvious display faults, you can also check whether the LED display has been damaged by physical impact, such as cracks, scratches and other physical damage.
Update software
Sometimes the software is not updated in time, which may also lead to playback errors, you can check whether the video control software is updated to the latest version.
Check whether overheating
LED display working time is too long leading to the overall temperature is high, can also cause the LED display screen uneven, low brightness and other display effect decline.
Steps to repair LED screen
Line detection
Resistance Detection
Use a multimeter to test the normal circuit board, record the value of the normal circuit board resistance, and then test the same point corresponding to the circuit board of the faulty LED display, and compare whether the values of the two tests are the same.
Voltage detection
Use a multimeter to detect the voltage to the ground at the problematic point, compare the obtained value with the normal value, and judge whether the voltage is problematic according to the value.
Short circuit detection
Detect whether the line is short-circuited need to close the LED screen to avoid damage to the ammeter, if there is a short-circuit problem, should not try to open the LED screen, should be dealt with short-circuit problems, so as not to open the circuit due to a short-circuit burned LED display of other electronic components.
Voltage drop detection
Use the diode voltage drop function to detect the voltage drop of different pins of the LED, check whether the value is the same, in general, the same type of integrated circuit board pin voltage drop value is the same.
LED display module failure
Single pixel dark, bad point repair
If the color is stuck in the bad point, can light but not able to change the color, this case of bad point using the control software to refresh can be solved.
If it is not luminous LED lamp beads, use a multimeter, black pen to connect the LED positive, red pen to connect the LED negative, if the LED lamp beads can glow, indicating that there is no problem with the LED, if the LED does not light up, you need to replace the LED lamp beads.
Replacement of LED lamp beads before the first to determine, LED display is a front access LED display or rear access LED display, if it is a front access LED display, directly from the front of the LED module can be removed, if it is a rear access LED display, you need to screw from the back of the LED module to take off.
After the LED module is removed, the first step is to remove the mask, use tweezers to remove the glue around the LED until the LED pins can be clearly seen. Then use tweezers to fix the LED beads, and use 40℃ to solder the LED beads to the PCB board.
Part of the module does not display, such as missing lines, missing lines
Observe the input direction of the LED module, from the input direction to see whether the first LED module with display failure cable connection is intact, the power supply or signal connection needs to be checked, you can repeat the unplugging and plugging of the power cord to check.
Observe the welding of the chip pins, whether there is a bad welding or short-circuit situation, if there is such a situation needs to be repaired, patch welding, or directly replace the chip.
Single LED module no display
- If a single LED module has no picture display at all, check the power connection of this LED module to see if the power supply is loose.
- If a single LED module has an image display, but the color is not right, it may be a signal input problem, disconnect the signal transmission line, and then re-inserted, the problem is still not solved then you need to replace the signal connection line to try.
- If you replace the cable, this LED module is still displayed abnormally, you need to check whether the interface of the PCB board is normal.
- If the above situation can not be solved, you need to replace the LED module.
LED display failure
Repeated display content
LED display shows repeated content, it may be caused by the missing cascade file, try to re-insert the network cable into the interface nearest to the sending card and re-send the cascade file.
Low brightness and blurred image
The overall screen display has low brightness and fuzzy image, it may be the problem of playback parameter setting, use the video control software to readjust the LED display playback parameters and adjust the minimum brightness value.
Display confusion or overlap
LED screen confusion may be the order of signal transmission line connection between cabinets have problems, need to check and reconnect.
It may also be a problem with the playback parameter settings, you need to change the playback setting parameters of the control system and reconnect the signal lines.
Check whether the Sending Card is working properly, if the Sending Card is abnormal, it needs to be replaced.
Flicker/Jitter
It may be that the sending card and receiving card are not working properly, watch whether the signal indicator light is on normally.
- Check the connection between the cabinet and the cabinet, reconnect the signal cable between the cabinets.
- Check whether the ground wire of the LED screen is connected normally.
- Check whether the DIV lines of the content source and the SENDING card are connected normally.
Part of the area is not displayed
- Check whether the LED module of the area without display is normally connected to power and signal.
- Check the playback parameter settings of the video control software.
No synchronization with computer display
The computer display screen of the content source and the LED screen are not synchronized, it may be that the setting of the DVI card is incorrect, under the mode of multiple display, the DVI card should be set to the “Repeat” option.
Multiple modules are not displayed
If a single line of LED module is not displayed, it may be a signal connection problem, if a corner of the LED module is not displayed, it may be a power connection problem.
LED screen system prompt not found
Check whether the various cables are firmly connected, and reconnect any loose connections.
The sending card may be damaged and needs to be replaced.
No driver installed, need to install the relevant software.
The whole LED display does not show (all black)
The whole LED display does not show, check the power connection, whether the LED cabinet’s indicator light is on.
If the power indicator light is on, you need to check whether the signal light is displayed normally, if the signal light is not on, check the interface of signal transmission, or change the line and reconnect it until the signal indicator light is normally on.
If there is no problem with the power cable and signal transmission cable, then you need to check whether the sending card and receiving card are connected properly, if there is no signal transmission, you need to try to replace the sending card.
Garbled code display
Check the signal transmission cable, try to unplug the signal cable, or replace the signal cable.
Check the connection between the sending card and receiving card, the green indicator light flashing means the connection is normal, the indicator light is not normal, you need to try to replace the sending card.
Check the video control system playback parameter settings whether there is a problem, try to reset the playback parameters.
When to contact professional LED screen repair service
Screen troubleshooting with no result
When you follow the above steps to try to troubleshoot your LED display and still can’t find the cause of the problem, you may need to contact a professional LED display technician for LED screen repair.
Some LED display manufacturers have long after-sales service, such as MuenLED, you can look for MuenLED to provide technicians to assist you in solving the problem when you encounter difficulties, and do not need to go to spend a lot of money to look for LED screen repair organizations.
When the screen is seriously damaged, for example, cracks appear
Individuals are able to solve malfunctioning problems only by replacing some simple components, if serious physical damage occurs to the LED display screen, such as large cracks or crushing, this level of LED screen repair or need to look for a professional technician to carry out inspections and repairs.
If operating the screen may jeopardize your safety
Some large LED display screen, or some hanging class, there are support columns overhead LED display screen, they are fault checking and repairing need to work at height, this situation to LED screen repair, try it yourself is a very dangerous thing, no safety, to find professionals to deal with.
Tips to increase the service life of LED screen
Regular cleaning of the surface
Regular cleaning of the LED display can prevent stains from affecting the screen viewing effect, but also effectively reduce the dust into the LED display, causing damage to the electronic components.
Keep the firmware up to date
Regularly replacing the fixings of the LED display and checking the interface can prevent the cabinet from falling and being destroyed due to rusty or loose fixings.
Ensure stable screen connection
An unstable power connection to the LED screen will cause the screen to flicker, and unstable current flow may cause damage to the internal circuitry of the LED screen, so it is best to give the LED screen a stable power supply environment.
Suitable working temperature
Try to run the LED display in line with the operating temperature of the manual, too extreme temperatures will lead to damage to the electronic components of the LED screen.
Use dust and moisture-proof cover when storing
If it is a rental type of LED display, sometimes disassembled and stored in a corner of the warehouse, it is best to use a dustproof moisture-proof cover for protection, to avoid water molecules and dust to enter the interior, damage to the electronic components.
Do not store LED display for a long time
Electronic equipment are not suitable for long time storage, long time not to use the LED screen, the equipment circuit may occur aging, subsequent difficulty in normal operation.
Avoid the impact of bad weather
Although the LED display screen can theoretically accept some rain and snow bad weather, but the premise is to ensure that you buy a high enough IP rating of the LED display, for example, the protection level of IP65 above the LED display can be used outdoors, but try not to use the LED display in extreme weather, which will greatly increase the load of the equipment operation.
Conclusion
LED screen is a costly display device, please try to operate it carefully during use to avoid it suffering physical damage.
Some regular simple cleaning and maintenance is a relatively low-cost behavior, but can better maintain your interests, if you encountered difficult to solve the problem in the process of use, you can contact MuenLED to help you provide solutions.