Solution: First, check if the switch's power indicator light is on and ensure the power source is properly connected. If there's a power switch, make sure it's in the “On” position. Problem 4: Certain displays do not show when using a KVM switch for your multi-screen setup. Each monitor. I have a secondary monitor that do not get any signal (black screen and power is on). I have been racking my brains trying to figure out why this is happening and trying various troubleshooting ideas to no avail. The visible symptoms are unmistakable: blank screens on switch, resolution. There are some quick tests that you can perform to rule out potential issues. Start by turning off all of the connected computers and peripherals, unplugging everything from the KVM, including power, and leaving it for 10 seconds.