If
your battery operated clock fails to run, make sure the battery is good
and installed properly.
The battery
has a "+" end and a "-" end. The movement is also
marked with a "+" and a"-". Be certain that you
install the battery correctly because it is possible to get it in backwards.
Also,
verify that the battery is good. Even if it is new, try it in some other
device to ensure that it has some power.