i lost my key somewhere in my house. since car has keyless ignition, is there a device that can "find" the key - like a metal detector for the car key?

 

The smart key is not an android/connected device. You'll have to search for it yourself.

 

Remove car door, bring it in the house, walk around while pressing the door handle button until the lock pops open and you'll be within a few feet of your key!

Just kidding.

It's a good question really. The key is able to transmit a fairly strong signal when you press any of the buttons but I don't think it's continually transmitting. (If it were you could probably "sweep" the room for listening devices and find it.) Instead I think it's normally only in receive mode listening for the car's request and then responding with a code.

This doesn't help you though, sorry. Check between the couch cushions.

 

Thanks for the replies. Even the disparaging and sarcastic first one. This is a good idea and some device must exist. The ignition can recognize when the key is in the car when I push the ignition button. So the key is necessarily must transmit a response, like sky says. I hope someone responds with the answer or is inspired to start a service like "Netflix" where the unfortunate can rent a key finder for a day. By the way good pint on checking the couch cushions; never would have thought to do that.

 

In reading a bit more from the service manual, I think I'm correct in that the fob doesn't continually transmit but only responds to a "request" transmitted by the car when you press any of the buttons. For instance when you press the unlock button on the driver's door the bcm sends the "request" broadcast to that specific antennae and the fob "hears" it and replies by transmitting the registered code on a different frequency. When you press the start button the "request" is transmitted inside the car to be sure the fob is present. Etc...

So, somebody with enough knowledge of the radio frequencies involved could certainly build a "proximity" locator which you could use to search your house and get within about 5 ft of your fob. (Transmits the "request" and beeps if it hears the fob's "response".) Not a bad idea really, every dealer should have one. The only catch is, this unit would only be one short step away from being able to capture the response code and then steal the car.....

 

Not exactly. You could probably locate the signal, but these systems use encryption and rolling codes so it would be really hard to even brute force the code.

Someone who knows the algorithms of how the rolling code is generated CAN steal the car, but that would be near impossible to figure out.

The easier way to steal would be to bring any Nissan key fob (new or old,) and then use a computer to attach to the BCM and reprogram the key to pair it with the BCM. This has been done many times by thieves and shown on different websites. Locksmiths already do this. All you need is Consult III computer, which can be stolen from dealers or the program hacked.

Good luck to the OP finding his key. If you don't find it, you can expect to pay quite a bit of money to get a new key. I believe I paid $250 for a new key and reprogramming, but the dealer ended up doing it for free since they damaged my BCM (their computer crashed in the process) and had my car for a week.

You can probably go to the local locksmith and buy a new key for yourself and get it done for much cheaper (around $100-150, including new key.)

 

Glad to hear about the rolling codes protecting our fobs. But yeah, I guess hacking the bcm would now be the most direct approach... Seems like a criminal with that level of knowledge should maybe consider a straight job. Ha!

OP, check the laundry hamper and the coat closet.

 

Does the car start? I had mine fall out of my pocket in the car and found it wedged between the seat and center console. After, of course, searching the entire house.

 

That's funny, I was just talking to someone about this the other day. I was using the lock button on the key fob to beep my horn so I could find my car in a parking lot. I remember saying it would be awesome if there was a similar feature on the fobs so you could use one fob to locate the other misplaced fob. Make it beep or something. Since both fobs are programmed to the same car anyway, maybe one fob can just as easily recognize the other without any issues with security codes.

Well, that doesn't really add anything helpful to the OP's current situation, but it's just an idea for the future. Good luck OP. Check the washing machine/dryer. Maybe you left them in your pocket or something.

 

I found mine in the dryer. Still works. I also lost it once deep in the seat after it fell out of my gym pants pocket. It will show up.

 

I posted this a few years ago, but when my wife lost her fob we thought at the time that our Golden Retriever swallowed it. To confirm we put the dog in her car to see if it would start (The dog thought he was going for a ride). Unfortunately, the car did not start. We found the fob later in a closet.

 

Got one for the GF for our house... it's like along came Polly when she loses her keys

 

I've seen these and considered getting it for years. Does it work well? What's the effective range?