A system comprising: - an implantable medical device (100, 102) - an accessory for use with a the medical device (100, 102) when said device is implanted in a mammal body, the accessory being adapted to be external to said mammal body and adapted to wirelessly transmit signals to said implanted medical device (100, 102) to initiate a backup function or a backup system in said implanted medical device, wherein the accessory is adapted to send said signals for initiating said backup function or backup system, wherein reception of said signals by said medical device makes said backup function or backup system override a built in control and/or powering system of the medical device (100, 102), wherein the accessory is adapted to send said signals as power signals wlrelessly to a receiver for wirelessly powering said Implanted medical device, wherein said signals comprises information regarding the backup function or backup system being coded into said power signals, and - a power source adapted to be implanted in a mammal patient's body for supplying power to the implanted medical device in the mammal's body, the power source comprising: - a receiver for wirelessly receiving power from a power source external to the patient's body, the receiver comprising a coil, and - a backup override system adapted to receive signals, wherein reception of said signals makes said backup override system trigger said backup function or backup system to override one or more other functions for controlling and/or powering said medical device, wherein said backup function or backup system is adapted to perform an emergency activity which comprises a predetermined activity in the implanted medical device chosen from at least one of the following: - running a motor, and - pumping using a pump, and wherein said backup system is further adapted to be powered by said wirelessly received energy for performing said predetermined activity. - an implantable medical device (100, 102) - an accessory for use with a the medical device (100, 102) when said device is implanted in a mammal body, the accessory being adapted to be external to said mammal body and adapted to wirelessly transmit signals to said implanted medical device (100, 102) to initiate a backup function or a backup system in said implanted medical device, - a power source adapted to be implanted in a mammal patient's body for supplying power to the implanted medical device in the mammal's body, the power source comprising: - a receiver for wirelessly receiving power from a power source external to the patient's body, the receiver comprising a coil, and - a backup override system adapted to receive signals, wherein reception of said signals makes said backup override system trigger said backup function or backup system to override one or more other functions for controlling and/or powering said medical device, wherein said backup function or backup system is adapted to perform an emergency activity which comprises a predetermined activity in the implanted medical device chosen from at least one of the following: - running a motor, and - pumping using a pump, and wherein - a receiver for wirelessly receiving power from a power source external to the patient's body, the receiver comprising a coil, and - a backup override system adapted to receive signals, wherein reception of said signals makes said backup override system trigger said backup function or - running a motor, and - pumping using a pump, and wherein