LED Screen Malfunction and solution

 LED Screen Malfunction and solution

Malfunction Status	Reasons for Malfunction	Analysis and Treatment of Malfunction
1. The entire screen is not enlightened or shows grids.	1. Whether the host computer is started 2. Whether the communication line is properly inserted. 3. Whether the transmitting card is properly inserted. 4. Whether the data line connecting media card, collecting card and transmitting card is properly connected. 5. The switch position of receiving card JP1 or JP2 is not correct.	• Start up the host computer • Properly insert the communication line. • Re-insert the transmitting card. • Properly connect the data line connecting media card, collecting card and transmitting card. • Adjust the switch position of receiving card JP1 and JP2.
2. Control system can not be found each time LED studio is started.	1. The data-collecting line between COM port and data-transmitting card is not connected or the computer’s COM port is broke.	• Connect the data line or change another computer.
3. The data at every 16 lines of the entire screen flashes or is constantly bright.	1. Check the setting up of the LED studio.	• Open up LED studio and select commissioning. Go to hardware configuration (password 168) and then select system configuration. Set the line sequence configuration into +0 or +1.
4. The entire picture sways or overlaps	1. Check the communication connecting the computer and the screen. 2. Check the DVI line of media card and transmitting card. 3. The transmitting card is broke.	• Re-insert or change the communication line. • Strengthen the DVI line insertion. • Change another transmitting card.

II. Driver Part

Malfunction Status	Reasons for Malfunction	Analysis and Treatment of Malfunction
1. Unit board is not bright.	1. Whether +5V power or GND is supplied. 2. Whether +5V power or GND shorts out. 3. Whether the OE signal of fifth pin of 138 is available. 4. Whether the OE signal connected to 245 is normal or not (turned off or shorted out).	• Give power of +5V or GND. • Disconnect the short circuit. • Provide OE signal. • Connect the turned off power and disconnect the short circuit.
2. The up-half part or low-half of a unit board is not bright or does not display properly.	1. Whether the OE signal of fifth pin of 138 is available1 2. Whether the signal of the 11th and 12th pin of 74HC595 is normal; SCLK, RCK) 3. Whether the OE signal connected to 245 is normal or not (turned off or shorted out). 4. Whether the SCLK and RCK signal of double-row pin connected to 245 is normal (turned off or shorted out).	• Provide OE signal. • Connect SCLK and RCK signal. • Connect the turned off power and disconnect the short circuit. • Connect the turned off power and disconnect the short circuit.
3. Previous line or a unit board or line of a corresponding module is not bright or does not display properly.	1. Check whether the pin of corresponding module’s line signal is insufficiently soldered or not soldered. 2. Check whether the line signal is disconnected with the corresponding pin of TIP127 or 4953 or shorted out with other signals. 3. Check whether the pull-up and pull-down resistors of the line signal is not soldered or insufficiently soldered. 4. Check whether the line signal output of 74HC138 is disconnected with the corresponding TIP127 or 4953 or shorted out with other signals.	• Fix the ones insufficiently soldered or not soldered. • Connect the turned off power and disconnect the short circuit. • Fix the ones insufficiently soldered or not soldered. • Connect the turned off power and disconnect the short circuit.