A method is provided for selectively providing power to at least one
component of a vehicle-based receiver module for determining the presence
and validity of a transmitted RF signal. The RF signal is a request
signal for activating a respective vehicle accessory function. Power is
provided to a receiver for a first period of time. The receiver is
operated to receive any RF signal that may be present from a remote
transmitting device. A received signal strength indicator (RSSI)
associated with operating the receiver is determined. A determination is
made whether the RSSI is greater than a first predetermined threshold.
The power is terminated to the receiver after the first period of time if
the RSSI is not greater than the first predetermined threshold.