Similarly, if the cellular call is disconnected by the network prior to
receipt of the termination tone, another call to the response center will
also automatically be dialed. The message ªREDIAL IN PROGRESSº will
be displayed on the message center and voice communication with an
operator will be restored.
During redial calls, full control of the cellular phone is returned to you.
Pressing either PWR or END on the cellular handset will terminate the
assistance request and reset the system.
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 ªSENDING LOCATION DATAº and ªDATA RECEIVEDº
will be respectively 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.
Global 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 20 000 km
(12 428 miles) 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
30 meters (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.
Controls and features
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