Ethernet Switch monitor

I'm working on project where I need to check whether the Switch is down. I have made an assumption that if a port is power down, switch is power down.
I want to check the voltages coming out from the rj45 cable connected to the switch port. But when i measured it from the multi meter i couldn't get a proper reading from any of the rj45 pins.

Is there a way to measure the voltages coming out from rj45.

AFAIK it's not an easy way to measure voltage in your normal ethernet plug. A possible solution would be to use a PoE switch, and then measure the voltage.