Hey guys and gals, I have a weird problem that I'm trying to help a friend with. She's an elderly woman that owns either a 2015 or 2016 RX350 (I'm pretty certain that it doesn't matter) and she has lost one her keyless remotes, INSIDE THE VEHICLE! Her son has looked for it, the Lexus dealer has looked for it, and I personally spent a good 1/2 hour yesterday looking for it...none of us have been able to find it! But we're pretty sure it's in there, as all you have to do is step on the brake and push the start button and the RX fires up...that and the fact that she cannot lock it with her second remote. Now she cannot lock the vehicle anywhere, anytime. I looked as well as I could without removing the seats. I took long, thorough looks into the underseat mechanisms, front and rear, in every cubby, every grocery bag she had in the car, the rear storage compartment, console, EVERYWHERE I thought that the remote could conceivably be. I spent a LOT of time on the rear seats which are kind of tricky with the 'webbing' under the cushions, which would prevent something that snuck between the cushion and the back, from reaching the floor. I found nothing!

So here's my question: does anybody know of some kind of 'detctor' that can lead us to where this thing is? Isn't the remote always putting out a signal to communicate with the vehicle? If so, is there any way to detect that signal, to help us find it? And if not, what's the cheapest way to get back to two working remotes for the vehicle? Is it to just buy another remote and have it and the remote she still has in her hand, reprogrammed, which (I think) will render the lost remote, useless?

Thanks for any help or advice that you can provide: she would like to be able to lock her vehicle again, especially when she's away from home.

 

I don't know about sniffing to find a remote, but have you checked between the upper and lower seat cushions?

 

Some time ago, my wife dropped the key fob while sitting in the driver’s seat. She didn’t know exactly where it had fallen — she’d just been moving her purse from the front passenger seat to the back of the car and knew it was somewhere inside. I searched all over but couldn’t find it. Eventually, I narrowed my search to the driver’s area. I couldn’t see anything under the seat, but I finally found it lodged deep between the seat guide and the center tunnel. It was impossible to see, so I used a long, stiff wire bent into a hook and kept fishing around until I caught it.

 

Same thing happened to me. It fell near the inner driver's seat rail where you could just barely see that there was something in there. Turned out to be the keyfob. It's so easy to fall out of the right pocket when fishing for something in the pocket. I was able to reach it by moving the seat forward and back and moving between the back seat and the front seat.

 

I'm surprised even the dealer couldn't find it. Maybe remove the front seats and go over them closely? The console?
If you're sure it's inside the car and it sounds like it is, shouldn't be all that hard.

 

Glove box ??

 

if you find it, add Apple Tag, nextime lost, its easy to find

 

Thanks nualarm: that's a great idea!

 

I looked really well in the glove box and the owner's manual 'jacket'...no luck. : (

 

If you're techniclly oriented, you can use a signal finder like this one
and trigger so that the lost key will send signal, I found this from internet

When Does a Lexus Key Fob Emit a Signal?

Lexus (and most Toyota/Lexus smart key systems) fobs emit radio signals in short bursts, typically under these conditions:

1. Proximity to Vehicle Door Handles

• The fob transmits a passive signal (e.g., 315 MHz or 433 MHz) when it senses the car attempting to read it (such as when someone grabs the door handle).
  
• This only happens if the car battery is connected and the system is awake.
  

2. When the Fob Button Is Pressed

• If someone presses lock/unlock or panic, it emits a stronger, active RF signal.
  
• But if the fob is lost under a seat or inside a compartment and untouched, it stays in a sleep mode.
  

3. When You Try to Start the Vehicle

• If the fob is in the cabin and you press the START/STOP button, the car sends out a signal request.
  
• The fob will respond only if it is within the cabin area, not in the trunk or cargo area (in some models).
  

4. Timed Heartbeat (Low Power Beaconing)

• Some Lexus fobs emit a low-power pulse every few seconds even when idle. This "heartbeat" signal is very weak and often only detectable by professional locksmith frequency detectors.
  
  Good luck
  
  

 

Look underneath/behind the gas pedal! I lost mine there and took a bit to find.

 

We had a guest with this situation and discovered the fob at the base of the windshield wipers,
outside the car but close enough to the sensors to be detected. By the way, there is a very large
difference between the 2015 and 2016 RX's, new generation with substantial changes. As for the
key fob, the 2015 had a somewhat oval shape with the buttons offset. The 2016 has the newer
rectangular fob with the 4 button all in a row. Same advice to locate however!

 

Thanks for all of the suggestions and ideas. And I did look around the base of the windshield wipers and a little bit under the hood, even though the owner has NEVER opened the hood herself. I feel like I would like to take another really good look under the gas pedal...problem is the car lives way on the other side of town, so I don't have access to it often. And I looked really long and hard in, under, and around those seat rails, thinking that it MUST have fallen down there, but I could not find it. I might take another shot at it, but my next opportunity to see the car won't come until Friday, and even at that, I have to drive 15 miles to go look for something that's not my problem. But I do appreciate everyone's ideas and suggestions...that thing HAS TO BE in there somewhere, and I'm having a hard time believing it can be THAT hidden!

 

Lexus key fobs use radio frequencies (RF) to communicate with the vehicle for functions like unlocking doors and starting the engine, so yes, in theory you can get an RF detector to try and locate the key fob. If you have a smartphone, there are apparently apps that can function somewhat like an RF detector.

 

this device should be able to detect the keyfob