05025253 is referenced by 167 patents and cites 34 patents.

An apparatus and method for monitoring the status of a multiple part vehicle. An apparatus according to the invention comprises a tag for placement on a second part of the vehicle. The tag communicates a unique ID code to an interface unit on the first part of the vehicle. The interface unit detects the presence of a valid ID code, and in response, provides an indication that the second part of the vehicle is connected. A transmitter provides data indicative of the connect/disconnect status of the vehicle to a central station. Vehicle position data may also be provided to the central station.

Title
System and method for remotely monitoring the connect/disconnect status of a multiple part vehicle
Application Number
258162
Publication Number
5025253
Application Date
October 3, 1989
Publication Date
June 18, 1991
Inventor
Kenneth W Paist
Philadelphia
PA, US
Michael Negin
Pennsauken
NJ, US
Stephan C Schifter
Philadelphia
PA, US
Joseph V DiLullo
Rydal
PA, US
Agent
Woodcock Washburn Kurtz Mackiewicz & Norris
Assignee
Secura Corporation
PA, US
IPC
G08B 5/22
H04B 1/00
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