When Monitored:
WARNING: This page is about a different car, the 2012 RAM Pickup and 2012 RAM Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The WIN monitors the VIN broadcast on the CAN C bus three times, when the ignition is turned to the RUN position. When the full VIN has been received by the WIN, all further broadcasts of the VIN are ignored for that ignition cycle.