An accessory (11) for use with an implanted medical device (100, 102) in a mammal body is intended for use externally to said mammal body and is arranged to wirelessly transmit signals to said implanted medical device (100,102). Said signals are sent in order to initiate a backup function or a backup system in said implanted medical device. The signals can be sent to initiate said backup function or backup system to override a built in control and/or powering system of the implanted device (100, 102). Also, the accessory can send said signals as wireless power signals to a receiver (102) for wirelessly receiving power in said implanted medical device, the signal information regarding the backup function being coded into said power signals.