I am working on a system from 1986. It has an old-fashioned 12VDC relay like the one in the picture.
When the circuit powering the relay coil is turned on, the relay does not switch on. When I unplug the relay and then plug it back in, with the circuit still on, it flips on.
While testing I found that the relay coil is only getting about 11.1-11.5VDC of the 12.5 that it should have (likely caused by corroded wires.)
Could this lower voltage be the issue? If so, why does taking it out and putting back in cause it to switch on?