On the main unit see if the red light comes on (indicating it is transmitting) when the wired chime rings. If not, there is a little manual trigger button (to the left of the battery compartment) press this for a second, if the red light lights up then it is transmitting. If the chime unit rings, it means the main unit isn't picking up the wired chime noise. This happened to me, for no apparent reason. By sticking the main unit directly on the top of the wired chime unit, the problem was solved.
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On the main unit see if the red light comes on (indicating it is transmitting) when the wired chime rings. If not, there is a little manual trigger button (to the left of the battery compartment) press this for a second, if the red light lights up then it is transmitting. If the chime unit rings, it means the main unit isn't picking up the wired chime noise. This happened to me, for no apparent reason. By sticking the main unit directly on the top of the wired chime unit, the problem was solved.
Check to make sure you don't have anything that would impede the connection at the battery terminal