kind of off topic but sort of the same
was this trick when testing a th400 automatic transmission on a 71 Buick
you would set the radio to an off sta. (between stations=static) in the lower AM band
and with the car in park eng. off /ign on depress the gas pedal all the way to the flood
and the radio should produce a 'pop' over the static,
this mean the kick down solenoid is working inside the pan off the V-body.

If your room light are on the same breaker as your outlets you will see them flicker when playing an EM