I have a Raspberry Pi 4 and it is connected to the 10.1" Touch Screen from SunFounder. A Relais is connected to Pi and the Pumps are connected to a 12V power supply. The 5V for the Relais comes from a different supplier. When the Pump is running, the display is black, but the program and the Pi are still running. When the pump stops, the display comes back and works fine. Where is the mistake?