Take battery out of the collar for several minutes and replace it with new battery. Make sure battery is installed properly.
Make sure the tab within the battery housing unit is making good contact. You may need to lift it up if it has gotten mashed down underneath the battery.
If the receiver collar has adjustable correction levels, try to change the level to level two or above.
Perform Short Loop Test (see section What is a Short Loop Test and how do I do one?)
If receiver collar still does not activate – remove a wire from the transmitter, try to change the levels. If everything appears to work normally, please contact our Customer Care Center to discuss replacing transmitter.
If receiver collar does activate – the boundary wire probably has a partial wire break. See section on “What is a partial wire break and how do I find it?”