Vehicle theft prevention system antenna monitoring system has control unit using direct current to monitor diagnostic impedance through connection cable

摘要

A vehicle theft prevention system antenna (16) monitoring system has a control unit (20) using a direct current to monitor a diagnostic impedance (12) through the connection cable (1) to determine if the connection remains intact. The antenna unit (10) separates high frequency and low frequency signals. Independent claims are included for vehicle theft prevention system using the antenna with monitoring system to handle active vehicle immobilization signals from mobile phone networks.