there are many kinds of problems in the use of led display screen. today, we summarize the “troubleshooting solutions for outdoor module power board of led display screen” and share them with you here.
a. the whole led display board is not bright.
1. check whether the power supply is connected to the signal line.
2. check whether the test card is used to identify the interface, but the red light flashing of the test card is not recognized. check whether the lamp board is connected with the test card at the same power source, or whether the lamp board interface has signal and ground short circuit, which causes the interface to be unrecognizable.
3. detect whether there is virtual welding short circuit in 74hc245, and whether the corresponding en signal input and output pins are virtual welding or short circuit to other lines in 245. note: mainly check the power supply and en signal.
b. in oblique point scanning, regular interlaces do not show overlapping pictures.
1. check whether the a, b, c, d signal input port to 245 is broken or virtual welding, short circuit.
2. detect whether the output terminals of a, b, c and d corresponding to 245 are open or virtual welding or short circuit between 138 and 138.
3. detect whether the signals a, b, c and d are short-circuited or whether a signal is short-circuited to the ground. note: abcd line signals are mainly detected.
c. one or more lines are not bright at full brightness
1. detecting whether the line between 138 and 4953 is open or virtual welding or short circuit.
d. in line scanning, two or more lines (usually multiple of 2, regular) are lit at the same time.
1. detecting whether the signals a, b, c and d are short-circuited.
2. detecting whether 4953 output is short-circuited with other output.
e. single or multi-point (irregular) non-bright at full brightness
1. find out whether the control foot corresponding to the module is short-circuited with the line.
2. replace module or single lamp.