User's Guide

5.3.3 Identifying FOBS within LF Range
Identify the available fobs by sending out a broadcast, which returns the Fob# in the selected fob field. Perform the
following steps to identify the available fobs within the LF range:
1. If not done already, follow the procedure detailed in 4. CARS Kit PC Evaluation Utility.
2. In the System Configuration window, choose Broadcast from the Selected Fob drop-down list.
3. Click the Fob ID button to send the broadcast request, as shown in the following figure. The available fobs
respond with their fob IDs and their Fob# assignments. The “Fob Vehicle ID” field displays the returned vehicle
ID.
4. Click the S/W Ver button to send the software version request to the fob. The “S/W Ver” field displays the
returned software version number.
Figure 5-5. Identifying FOBS in Range Test Window
Notes:
• To use the broadcast function, it is recommended that only one fob be within range, and it must have a
battery inserted in the battery socket.
• Fobs that are not paired with the current system or that have a different vehicle ID, can also be identified
as within range. If the located fob is paired with the system, the selected fob index changes to the
location in the system where the fob is believed to be stored. It is recommended that the fob ID be
verified by checking it against the list of learned fobs.
5.3.4 Fob Calibration Overview
In a PEPS system, the learned fobs receive the LF signal and measure the magnetic field strength as an RSSI value.
This value is reported to the vehicle and determines the fob’s position with respect to the transmitting LF antenna. To
ensure RSSI accuracy, the fobs must be calibrated, including normalization and compensation, along all the three LF
ATAN0219
System Operation
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User Guide
DS50003051A-page 19
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