Enhancement for power-down sequence

摘要

When a cellular telephone is powered down, it sends a power-down message to a network it was registered with. If the cellular telephone does not receive an acknowledgement of the power-down message from the network, a flag is set in the cellular telephone. The power-down sequence is concluded by the cellular telephone, and the cellular telephone is shut off or put into a reduced power consumption state. When the telephone is turned back on the flag is evaluated to see if it was set during the course of powering down. The status of the flag when the phone is powered up is then used by the cellular telephone to determine whether it should make a network access request to a network the telephone was registered to, during the power-up operation in order to cause that cellular network to update its database regarding the whereabouts of the powered-up cellular telephone.

主权项

1. A method of restoring wireless communications to a wireless communications device, after the device is powered down, the method comprising:
receiving a power down message from a telematics controller of a vehicle in response to the vehicle being shut off; initiating a power down sequence in response to receiving the power down message; transmitting a power-down registration message to the network in response to initiating the power down sequence; waiting for a network response message to the power down registration message; if the network response message is received, powering down the device according to the power down sequence; if the network response message is not received within a finite period of time, setting a flag within the device and powering down the device according to the power down sequence; wherein setting the flag comprises setting a value of at least one binary digit, the value of the binary digit when set indicating whether the network response message was received or not received.