Hi there, there are actually multiple antennae pick ups around the car.
by each boor and the trunk
they rarely fail either, although they do on occasion.
anytime someone has an issue such as yours, I would first tell them to replace the batteries in there remotes since you can get a set of 2 batters for under $5
then I would tell them to remove there FOB off there keys in case they have a speed pass or something similar interfering with the RFID signal
let me know how you make out with this please.