Location Data Retransmit Capability
During an activation, the Lincoln Security Response
Center operator has the capability to initiate a
retransmission of the electronic data message. This
may be necessary to ensure a more precise
determination of vehicle location or to track a
vehicle that is moving. To accomplish the
retransmit, a special tone is sent to the vehicle by the
response center. In this situation you will
temporarily lose voice contact with the operator and
the messages "SENDING LOCATION DATA" and
"DATA RECEIVED" will respectively be displayed
on the Message Center. After the data
retransmission is complete, voice communication
will be restored and the CID, LAT, LON and HDG
message will again alternately toggle on the
Message Center display.
152Global Positioning System
Vehicle location is continuously updated via
Global Positioning System (GPS) technology.
GPS was developed by the U.S. Department of
Defense for worldwide navigational and
positioning purposes. It utilizes a constellation
of 24 orbiting satellites located more than 20
thousand kilometers above the earth. At any
given time, several of the 24 satellites should be
visible to the vehicle's GPS receiver. Based on
the time for signals emitted by these satellites to
reach the receiver, an on-board computer will
determine the vehicle's location, typically within
100 feet. In addition to latitude and longitude,
the system also determines heading and speed.
Vehicle positioning information is relayed to the
Lincoln Security Response Center ONLY
during roadside or emergency requests. The
response center will not be able to track your
location while in an inactive state.
Positioning capability temporarily degraded after
battery reconnect
When your vehicle is started, the Lincoln RESCU
GPS receiver begins the process of determining
vehicle location. The receiver will search the sky
and attempt to acquire signals from all visible
satellites. A real-time clock and an almanac
containing detailed information about the satellite
constellation are stored in the on-board computer's
memory and are used to expedite the search. If the
vehicle's battery is disconnected, the clock memory
is erased and time and date are lost. Once the
battery is reconnected, it could take approximately
15 minutes to reacquire the clock and for
positioning capability to be restored. During this
time, the system will operate but the response center
will not be able to identify your location. In this
situation, the operator will depend on you to
provide verbal information regarding vehicle
location.
154Inoperative if cellular signal marginal or
unavailable
Since the Lincoln RESCU System utilizes the
vehicle's cellular phone, it can only be operated
in geographical areas with cellular coverage.
Although approximately 90 percent of the U.S.
population lives and works in cellular coverage
areas, there are various rural or mountainous
areas where coverage is marginal or does not
exist. If an activation occurs in this situation,
the messages "NO CELLULAR SIGNAL" and
"WAITING TO ACQUIRE" will alternately be
displayed on the Message Center. If after
several attempts cellular service cannot be
acquired, the message "UNABLE TO PLACE
CALL" will be displayed, the assistance request
wfll be terminated and the phone will return to
its normal operating mode.
