I have a motorcontroller and a motor and they sit next to each other. The motor shaft has a photointerrupter sensor and the sensor signal is connected to the motorcontroller. The motorcontroller has a feature where it will shuts off the motor whenever it senses a spike in the motor's RPM. The problem that i'm having is that whenever I tap into the photointerrupter sensor using a wire, the motorcontroller shuts off the motor like there is an RPM spike. It acts the same way even if the wire i'm taping with is not connected to anything. My theory is that the wire acts as an antenna and it is outputing spikes created by the motor ecm. The motor controller mistaken these spikes as an increase in RPM and shuts off the motor. What can I do to overcome this problem??