Wireless key for unlocking a vehicle and/or for enabling a function of the vehicle

A wireless key for unlocking a vehicle and/or for enabling a function of the vehicle, comprising

• a sensor for motion detection, an evaluation unit, and a transceiver which is designed to signal its availability as a connection partner and to wirelessly transmit data to a connection partner and/or to receive data from the connection partner;
• the transceiver has at least one operating mode and at least one sleep mode where an energy requirement of the transceiver is lower than in the at least one operating mode,
• the evaluation unit is designed to switch the transceiver from the operating mode to the sleep mode if no movement is detected by the sensor within a predetermined interval and to switch the transceiver from the sleep mode to the operating mode if a movement is detected by the sensor,
• the transceiver is designed to broadcast advertiser events on at least one advertiser channel to signal availability as a connection partner,
• the transceiver has a first sleep mode and a second sleep mode,
• transmission of the advertiser events is stopped in the first sleep mode and a connection with the connection partner is terminated and the transceiver is completely switched off in the second sleep mode, so that the energy requirement of the transceiver is lower in the first sleep mode than in the at least one operating mode and lower in the second sleep mode than in the first sleep mode,
• the evaluation unit is designed to switch the transceiver from the first sleep mode to the second sleep mode if no movement is detected by the sensor within a predetermined second interval,
• the transceiver is designed to establish a connection to the connection partner in the first sleep mode and to stop signaling availability as a connection partner,
• the transceiver is designed not to initialize itself after switching from the first sleep mode to the operating mode and to initialize itself when switching from the second sleep mode to the operating mode, so that the transceiver connects to the connection partner more quickly after switching from the first sleep mode to the operating mode than after switching from the second sleep mode to the operating mode.