Not detecting key fob or card - vehicle goes into hibernation (1 Viewer)

[richord]

This has happened a number of times recently. I replaced the battery in both the key FOB and card and it's still fails.

I go to pick up my grandson at school. I get in the pickup line and stop the GX 550 and stay in the vehicle. I can hear the computers shutting down and the last screen message after a few minutes is the exit warning is turned off. The dashboard goes dark. I sit there for about 5 to 7 minutes.

When I try to start the vehicle pushing the start button, nothing happens. No messages at all. After I try pushing the start button 3-4 more times, I may get a message "key not detected" or "put the key close to the start button". The vehicle then starts.

This is the only situation when I get this problem.

I have a suspicion that if you shut down the car and stay in the vehicle without opening a door, the car literally goes into hibernation and will not even attempt to detect the key after a set time delay until you open the door or touch the outside door handle or push the start button numerous times.

Has anyone experienced this?

 

[Mike'sGX]

Sounds like RF Interference coming from the school. Possibly surveillance cameras, other surveillance or fire detection devices.
Big Brother government is watching you.

 

[richord]

RF energy that would block the communications between the key fob and the vehicle that close together would have to be so strong it would affect many other devices using radio communications as well as other cars who are also in line. Also, there is a pattern to this, that has to do with stopping the car and not exiting. I've parked near the school to go into the building and returned to the vehicle and the key fob worked fine.

I suspect that Toyota added some additional protection to prevent criminals from duplicating the key using devices that are for sale on Amazon and others. It is very easy to pick up those signals and duplicate a key.

 

[Mike'sGX]

richord, you are correct regarding the need for a strong RF signal but a low power RF signal of the correct wavelength carrying a digital signal could confuse the start mechanism of a vehicle.

I had a very low power X-10 IR to RF converter / repeater installed in my house that prevented a Jeep Cherokee parked about 15 feet from the repeater from using the pushbutton starting. Placing the keyfob next to the start button would start the vehicle, same as the original post above. Once I unplugged the X-10 repeater the Jeep started fine. I could repeat the start problem by simply plugging in the RF repeater.

Moving the vehicle about 5 to 10 feet also solved the problem.

OK, Now having said all that --
Could you recreate the start problem by recreating what you did at the school by not opening the door after shutting down the GX? I agree, that sounds like what really happened. I might try that with my GX.

 

[richord]

I can see how the X-10 signal could affect other devices if they are in the same frequency band. I recently discovered that when I had my GX fob and my Land Rover fob in the same pocket, the GX fob did not work to unlock, but that occurred in my driveway. I think the Land Rover can be unlocked with a TV remote given the quality of their electronics.

I read earlier that some folks had discovered that on some vehicles, including Lexus, the key fobs stop transmitting after about 5 to 7 minutes if the fob is not moved. The fob supposedly has a motion sensor in it. This is to reduce the possibility of your fob being scanned. Lexus seems to have started to add this feature in 2022/23.

If that's the case, it may explain why my key stops being detected. The next time this happens I'm going to try to shake the fob and see if it "comes alive". I also have an EMI broadband detector that I can use to monitor if the fob is transmitting. I just tried it, and it registers the transmission when I push one of the buttons on the fob.

I also learned that you can manually turn the fob off by pushing and holding the fob lock button and clicking the unlock button twice. This works, I just tried it. After i did this the fob will not unlock the car unless I pushed one of the buttons. I'm going to check the manual to see if there's any reference to this feature.