A method and a system of controlling a PLMN scan rate (PCR) in a vehicle telematics unit. The method carried out by the system includes the steps of: (a) determining a power condition that includes a powered mode, an unpowered mode, and a DRx mode; (b) determining whether the telematics unit is scanning one or more home networks or one or more visitor networks; and (c) setting the PCR based on the determined power condition and the determined network, including: (c1) when in the powered mode and scanning a visitor network, the PCR is set to a first scan rate; (c2) when in the powered mode and scanning a home network, the PCR is set to a second scan rate that is slower than the first rate; and (c3) when in the DRx mode, the PCR is set to a third scan rate that is slower than the second rate.