The troubles that often occur in onboard LED advertising screens are black screens, display screens, and advertisement delivery failures. Therefore, for maintenance personnel, it is necessary to understand what causes this phenomenon and facilitate troubleshooting.

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. When the power supply is normal, black screen, open the display screen, initially observe whether the indicator light of the control system is on. If no indicator light is on, use a multimeter to check the input and output voltage of the power supply. Under normal circumstances, the output voltage of the power supply is 4.5V. To 5.5V.

3. If the output voltage of the power supply is normal, the indicator light of the control system is off, indicating that the system is faulty. If only the system power indicator is on, the status indicator is off (normally the system has a power indicator, the work indicator blinks. ).

4. If the power indicator is on, and the system indicator flashes normally, the control system hardware is normal. Use this test software to check whether the system has been set to “Time-based screen” (if the system is set to be on Screen, need to reset the system) or re-upgrade the control card, and check whether the power supply of the unit board is normal (check whether the unit board unit board power supply is not welded).

Second, car LED advertising screen or display abnormal

1. The description of the LED screen display on the vehicle is the hardware failure of the cell board. The common faults are the die management and welding (one column is not lit, one is not bright), the chip is burned out (the second half is not bright), and the lamp beads are burned out. Bright or one is not lit

2. If one column is not bright, please repair the corresponding chip and then teach it. A small part is not bright, you need to replace the corresponding chip (column control chip 5020 or 74H595, line control chip 4953)

Third, the vehicle LED advertising screen display is normal, but the ad delivery failed

1, first check the communication line, whether the communication device plug off or unplugged, if yes, please call back, (GPS to the display has two connectors, one is connected to the GPS, the other is led display external communication line 50 There is a connector at the centimeter

3. If the connectors are all connected, try to unplug the communication connector at the display and check if there is any bad contact on the connector copper piece or if the copper piece has been inserted incorrectly. If so, try to correct it. (In this case, the advertisement has already been displayed, but the platform display is being sent, indicating that the LED's feedback line (TXD) is faulty. Please check whether the connector is mated properly.)

4. If the connector at the display screen has been connected and the display screen communication is normal, check whether the connector at the GPS is disconnected or whether the communication line at the display screen to the GPS is short-circuited.

5. If it is judged to be a display problem, open the display and check whether the communication line of the system falls off (the display is relatively rare). If the communication line is normally connected and the system's communication line chip (232) is faulty, this happens. Need to replace the communication chip.