Power management for subscriber identity module

A system for controlling power to a removable user identity module (SIM) in a wireless communication device (WCD), the system comprising:

• a power source coupled to the SIM;
• and
• a processor that controls the power source to:
• (a) supply power from the power source to the SIM when a request from the WCD is pending for service by the SIM,
• (b) supply power from the power source to the SIM when a software module running on the WCD requests maintenance of power to the SIM, and
• (c) terminate power to the SIM when no request from the WCD is pending for service by the SIM and no software module running on the WCD requests supply of power to the SIM.

A computer-readable medium containing instructions that cause a programmable processor to:

• supply power to a removable user identity module (SIM) when a request from a wireless communication device (WCD) is pending for service by the SIM;
• supply power to the SIM when a software module running on the WCD requests maintenance of power to the SIM;
• and
• terminate power to the SIM when no request from the WCD is pending for service by the SIM and no software module running on the WCD requests supply of power to the SIM.

A method comprising:

• storing a user access code associated with a subscriber identity module (SIM) in a memory associated with a wireless communication device (WCD);
• retrieving the user access code from the memory when power is resupplied to the SIM;
• and
• using the retrieved user access code in a security authorization process to authorize use of secure features of the SIM.

A computer-readable medium containing instructions that cause a processor to:

• store a user access code associated with a SIM in a memory associated with a WCD;
• retrieve the user access code from the memory when power is resupplied to the SIM;
• and
• use the retrieved user access code in a security authorization process to authorize use of the WCD.