Bus led srceen is installed in the car, the use of special power supply, control card, unit board manufacturing through the dot matrix light off display text, pictures, animation, video equipment. It is with the rapid development of LED display screen and independent of a set of LED vehicle display system, and ordinary door screen, fixed not mobile LED display screen, compared to its stability, anti-interference, anti-vibration, dust and other aspects of the higher requirements. Usually LCD display with external sound, readable SD card, USB and Bluetooth and other functions. You understand the composition, performance requirements and functions of the vehicle-mounted LED advertising screen, but do you know some of his common failures and how to solve these failures should occur? For the maintenance of LED display screen personnel, it is necessary to know these basic knowledge, convenient in the maintenance process for troubleshooting solutions.
Car LED screen common faults are as follows:
First, the car LED advertising screen black screen
1, the power supply is not normal, the screen normal operating voltage is DC 9-40V
2, black screen under normal power supply, disassemble the display, preliminary observation of the control system indicator is bright, if it does not happen the indicator is bright, please use a multimeter to check the input and output voltage of the power supply, under normal circumstances, the power supply output voltage is 4.5V to 5.5V.
3, if the power supply output voltage is normal, the control system indicator lamp does not light up, that is, the system failure, if only the system power indicator lamp is always on, the status indicator lamp does not light up (normal condition system has power indicator lamp is always on, the work indicator lamp flashes).
4, if the power indicator is always on, and the system instructions are also flashing normally, indicating that the control system hardware is normal, this situation using the test software to check whether the system is set to “school hours on the screen” (such as the system is set to school hours on the screen, you need to reset the system) or on the control card to re-escalate, and to check the power supply of the unit board is not Normal (check the unit board unit board power supply has no welding).
Second, the car LED advertising screen screen or display abnormalities
1, car LED screen screen shows that the unit board hardware failure, common faults are chip tube teach soldering (a column does not light, a small piece does not light), chip burned out (the second half of the part does not light), beads burned out (a column of light or a column of light, etc. does not light)
2, such as a column does not light, please patch welding the corresponding chip can be taught, a small part does not light, you need to replace the corresponding chip (column control chip 5020 or 74H595, line control chip 4953)Third, the car LED advertising screen display is normal, but the ads send failure
1, first of all, check the communication line, communication machine plug is off or pulled out, if so, please connect back, (GPS to the display has two connectors, one is docked to the GPS, the other is led display external communication line 50 centimeters at a connector)
2、If the connectors have been connected, try to unplug the communication connector at the display, check whether the copper piece of the connector has poor contact or the copper piece has been inserted biased, if so, try to correct it. (In this case, the advertisement has been displayed, but the platform shows that it is being sent, which means that the led's feed back line (TXD) is faulty, please check whether the connector is docked well).
3、If the connector at the display has been connected at the same time to judge the display communication is normal, please check whether there is a phenomenon of falling off the connector at the GPS or whether there is a short circuit in the communication line from the display to the GPS.
4, such as judgment is a display problem, dismantle the display, check the communication line of the system has not fallen off (fall off display is relatively rare), if the communication line is connected to the normal judgment is the system's communication line chip (232) failure, this situation requires the replacement of the communication chip.
Above is the car display screen appears black screen, screen or display abnormalities, ads sent failure of some of the basic solutions!