I have three fobs for my Prius. Yesterday, for a while, I thought I had lost one of them. This got me to thinking about the risk of having someone find the fob then go around the block until he found a car that would respond. As it happened, I found the fob. My question: in the event someone lost their fob, could the remaining fob be reprogrammed and the code for the lost fob removed from the car's computer?
Losing a fob could be a real problem. All a thief has to do is get within about 30 feet of your car and press the red alarm button. The horn sounds to locate the car, and then he just presses the unlock button to silence the alarm. The car is now quiet and unlocked. The car has a list of which fob numbers work with it. If you lose a fob, that fob can only be deleted by updating the list in the car. Any Toyota/Lexus dealer, or any other mechanic with a Toyota scantool can change the list. It should take about a half-hour's labor. I figure you need at least one fob per driver, plus an extra as a backup. A lot of eBay keyfobs don't work as smart keys, or even with the remote functions. But for a backup, that really doesn't matter. All you really need is a mechanical key to get in the door, and a keyfob that works when plugged into the keyslot in the dash. Just about any used keyfob can added to the car's list of acceptable keyslot keys. For a full function smart keyfob, you may have to pay full fare to a dealer.
