In Case Of Abnormal Conditions - Sharp EL-2901RC Operation Manual

IN CASE OF ABNORMAL CONDITIONS

When this unit is exposed to strong RF noise and/
or extreme physical shock during the operation, or
when the power cord is plugged into the AC outlet,
the unit may start functioning abnormally which, in
some rare occasion all keys - including the power
key and the key - cease to respond.
If such abnormal conditions are observed, unplug
the AC cord from the socket. Keep the unit
unplugged for about 5 seconds, reconnect the AC
plug, then turn on the power.
9