Low Frequency Antenna

In vehicles equipped with the optional PEKG system, when the status of the ignition switch (KIN) transitions to ON it provides a hard wired input to the BCM and an electronic message input to the RFH over a dedicated Security K-line data bus. The RFH relies upon three Low Frequency (LF) antenna units to challenge the Sentry Key transponders using a LF signal, then monitors responses from the Sentry Key transponders received as Very High Frequency (VHF) signals. The RFH determines whether a valid key is present based upon the response from the transponder.

If a valid key is detected, an electronic valid key  message is broadcast by the BCM (without PEKG) or the RFH (with PEKG) over the CAN-C data bus, and the alarm will be disarmed. If the PCM receives an electronic invalid key  message from the BCM or the RFH, or receives no message from the BCM or the RFH over the CAN-C data bus, the alarm will continue in the active state.