Jeep and proximity key

[dieseltojo]

When you go just far enough that your car will not open, put the sender to your head and press it again . it will open the door.

No joke as I have tried it when a mate forgot to lock his car......Yep he didn't believe it either.

But he does now.....

[Azhure]

Our Landcruiser's proximity smart key will only allow the car to start if the key is within a couple of feet of the car maximum. Once the car is started it will keep going if the key is taken further away but it keeps giving alerts about missing key. The proximity key also has to be within a couple of feet or even less of the door for it to open automatically, but pressing the unlock button on the key will unlock it from a long way away.

My guess is the owner of the Jeep started the car then went back inside with the key in hand, allowing the theives to drive it away and keep driving it until they turned it off.

[dnsoakeshott]

No, OT i have tried it a few times and i need to be within about 30 foot of the car to get it open. If the keys are not in the car, the car will not start. As a previous poster said you get the message on the dash 'key fob not detected'.

[Old Techo]

C'mon OT, you cannot see 200m

As a Techo I'm keenly interested in the range of a transmitter and receiver in the form of a key fob and vehicle. The most common place for me to test mine is when travelling and we stop and walk out to the end of a jetty. Typically there is nose-in parking in the open where our vehicle can be seen as we walk out along the jetty.

When we visited Walhalla there is a walking track along the side of a steep hill and one can look directly down on the town and main road. I say main road but there is only one. From this height of maybe 20 metres above the road it was ideal line-of-sight to test the key fob range and I was very surprised when it worked at an estimated 300 metres. The distant flashing lights were barely perceptible to the old naked eyes.

PS - on a dull day I can see my neighbour's turn indicator as they slow for their driveway nearly 400 metres beyond our gate. I just measured the distance on Google Maps

[Old Techo]

No, OT i have tried it a few times and i need to be within about 30 foot of the car to get it open. If the keys are not in the car, the car will not start.

As I mentioned, maybe it is a security issue and they have deliberately reduced the fob door opening range.

Re keyless starting it would also be very important that a vehicle could not be started if the fob was even just outside as you may have kids fiddling whilst the driver was wandering around the outside of the vehicle checking, or even changing a flat tyre.

[Azhure]

Re keyless starting it would also be very important that a vehicle could not be started if the fob was even just outside as you may have kids fiddling whilst the driver was wandering around the outside of the vehicle checking, or even changing a flat tyre.

I know the Landcruiser will not start and if left running will be complaining loudly and often about missing key if the key is as far away as the tyres. When my husband has left the car running while using the compressor to put air in the tyres with the key in his pocket it does just that non stop.

[PeterD]

C'mon OT, you cannot see 200m

As a Techo I'm keenly interested in the range of a transmitter and receiver in the form of a key fob and vehicle. The most common place for me to test mine is when travelling and we stop and walk out to the end of a jetty. Typically there is nose-in parking in the open where our vehicle can be seen as we walk out along the jetty.

The antenna for the vehicle security system is commonly mounted at the base of the windscreen. With nose on parking the vehicle would be tilted a bit nose down. Add to that the transmission is over water. The jetty would also give you the advantage of extra elevation. In addition you would not be getting cancelling reflections from close objects. Add all these things together and I can see that you would get heaps more range than being in close proximity in a car park.

When we visited Walhalla there is a walking track along the side of a steep hill and one can look directly down on the town and main road. I say main road but there is only one. From this height of maybe 20 metres above the road it was ideal line-of-sight to test the key fob range and I was very surprised when it worked at an estimated 300 metres. The distant flashing lights were barely perceptible to the old naked eyes.

This is an excellent example of how good clearances assist with radio transmissions. A similar example I encountered was working on an airport ILS antenna system. We had some flea power aircraft band (120 MHz) transceivers. They would not communicate to each other over 300 yards yet you could use them to talk to flying aircraft. For the technical minded, it is all tied up with Fresnel zone clearances. Look it up if you are interested.

[dieseltojo]

Peter you have me thinking of what I posted about putting the key to you head and getting a result over a distance.

Maybe all that I did was to raise the elevation of the key rather than to have anything to do with the rather thick bone density (stated by others) of my head.

[Old Techo]

DT, no reflection on you (pun intended) but perhaps the metal plate in your head is of parabolic shape?