Just bought an 09 prius. Had to open door with metal key and start car by plugging in the key. Both keyless and buttons on fob don't work at all. Replaced battery on fob and red light works. Aux battery good. Disconnected it for about 10 mins. Still didn't work. Key button under steering wheel is out (on) I did the "chicken dance" procedure and this was interesting. I only have one key. I did the procedure to program a new key just to see if it would help. What was interesting is that at the end of the procedure you are to press the lock and unlock buttons on the fob. When I did this, the car would lock and unlock. Unfortunately after the procedure my problem hadn't been resolved. This leads me to believe the key and car are both able to detect each other (at least as far as remote entry) but something is stopping it from working. I know it's a common topic but I don't see any solutions so far online.
So do you know if this fob has ever worked to (remote or keyless) unlock/lock this car. I suspect the previous owner bought a secondhand fob and only set up the RFID portion of it so it will deactivate the immobiliser and allow the car to start. You probably will need to remove all registered keys, reseed the immobiliser, and add the key back. If you do do this, get another key fob and add that as well. Someone else will need to chime in to confirm whether the second key needs to be brand new or a secondhand one will work, I can't remember what the verdict on that was.
Ditto. When we bought my wife's '07 several years ago it only had one fob and it was fully functional. The dealer had a used fob laying around that he was able to make work like yours. I used that one since I didn't drive the car often. I had an old fashioned car key made that I kept on my key ring and then plugged in the fob to start the car. We didn't spend the money to get it reseeded since I used it so rarely and we did actually have the two fobs. If you just have one fob and that's how it works, you'd be wise to get that taken care of by a dealer or locksmith so you have two fully functional fobs. It's not very cheap, but if you lose that fob you're kind of SOL. Hopefully, you got a significant discount on the purchase price that will cover that expense.
I can't be sure if your situation is identical to what we had on our '07, but our add-on fob did not open the doors. No chicken dance involved. The dealer used the official Toyota Techstream software, so he got that fob as good as it could get.
