2012 Prius. I lock the doors manually, close the door. Seconds later my car starts buzzing and a message on the console reads 'key detected in car'. The key is in my hand. I can then click the lock button on the fob and everything is fine. I changed the fob battery. No change. I made sure all doors and back hatch were closed. No change. There is definitely not another fob in the car. Any ideas? Thanks!
I respectfully suggest that you do not KNOW that .......yet. Remove the mechanical key from the FOB. Leave the FOB very far away, like at least 100 feet. Enter the car. Close the door. Open the door, exit and lock the door with the key. IF......it still says "FOB in car" there is a good chance that there IS and you just haven't found it yet. While inside the car without a FOB, you can also try to start it with the push button. If it starts.............well, you know.
FYI: You posted this in the Prius v forum (the wagon, not the hatchback). You mention the message on the console, and a 2012 Prius V does not have the "Multi Info Display" where the message you described appears. Not a problem... the advice given above still makes sense. If you post about your 2012 in the future, posting it in the Gen 3 Prius forum might get you a better answer, faster. If your problem is not caused by a 2nd fob, you are probably looking at an issue with the bluetooth receiver either in the "Start Button", or the driver's door handle. If you have a higher trim level, you might have multiple door handles with receivers. It might be useful to know what happens when touching the ribbed spot on the top of the drivers door handle towards the front. It should lock the car if your key is in your other hand, or in your pocket. IMHO, it is easier than locking the door while still in the car.
And... I'm an idiot. @sam spade 2 was correct. I found my wife's keys under the passenger's seat. Ugggh! Thanks, everyone, and sorry for wasting your time.
In all likelihood, you won't be the last person to experience this problem. Hopefully this thread will help others out.
It wasn't a waste of time. This exact scenario has played out many times to many Prius owners (including myself). Consider it a rite of passage. It is nice to remember those innocent days before Oil Consumption , Clogged EGR passages, or Inverter failure kept me up at night.
Heed what the machine tells you. The machine is perfect. It never lies !!!!!! Sorry, couldn't resist.