System says "Warning ....motion sensor not responding."

@numan27, the motion sensor is not communicating with the base. You should be able to use the keypad (or dashboard if you are on the 24.99 plan) to know which one it is.  Try changing the battery, and if that works, call SS to report it and they will send you a new battery. If that's not it, could be defective motion sensor which SS will replace at no cost under the 3 year warranty.

The sensor may be too far from the base, have too much material (particularly metal) between them, or have some gizmo producing interference.  If the battery does not fix the problem, try swapping the motion sensor with one which does not give a problem.  That will show whether the problem is the sensor (if the same problem occurs at the other location) or the location (if the other sensor starts showing the same problem).

ABSOLUTELY SAME ISSUE HERE !!   I have all my four motions set to max sensitivity. I can hold the motion in my hand and it still wont trigger !  Base station within range no issue.  We will have to get multiple motion units now.  Loosing trust !