Yes, they can be reprogrammed (actually married to your car). Be sure to take all your ikeys with you to the dealer. Also, most of the ones on ebay have cut keys which will obviously not work in your lock.

As for no battery function, they should still work. I'm not 100% sure, but I see no reason they don't function like security access cards like the kind you wave in front of a reader for building access.

 

Well, rather than remove the battery, there's a much easier way--just wrap the spare fob tightly in tin foil before putting it in the glove box (or wherever you wish to leave it in the car). The tin foil acts as an RF shield, preventing communication between the key and the car, and the battery can stay in the fob.

Just tried this in my G35S. The door locks would not work, and I got the "no key" message when I tried to start the car. removed the foil and everything worked normally.

This is so simple it's kind of a forehead-slapper....

 

Sorry to hear that...Sometimes these technology are more inconvenience...

 

Personally I feel safer taking the battery out. Say the foil trick for some reason didn't work and at the same time a theif is walking around pushing the door button.

I don't even feel 100% secure even taking the battery out b/c it just defeats the immobilization capability since the key will start the car if you put it in the dock.

 

Wouldnt removing the battery be best anyway? ( in terms of drain on the battery , given the fob is always putting out a faint signal)

I would keep them apart and keep them seperate...eg battery in a thin sleeve in the glove compartment ; fob in a small jewellery box in the trunk. Only need to assemble during an emergency ( eg prirmary fob screws up)

TMG

 

Agreed, except that we have not established that the fob won't eventually loose its memory if the battery is out for an extended period. Per my previous post, some memory technologies require constant (but low) power, and use a capacitor to supply energy while the battery is being replaced. That's why I suggested leaving the battery in and disabling the fob via RF shielding. Otherwise you could be stuck with a back-up fob that also doesn't work just when you need it.

Anyone willing to remove a fob battery for a month or two then reinstall the battery and see if it still works? I'm not, because if it it does loose its memory I've got to pay the dealer to re-program both fobs.

Also, it's not clear that the fob is always putting out a signal. I don't know for sure, but I believe the fob transmits only when a button on the fob is pressed or when it receives a recognized signal from the car. For example, when you walk up and press the door lock button on the door handle, the car transmits an inquiry to the fob; the fob replies with it's unique code and the car then verifies that it is an associated fob. Otherwise the battery drain would be too high.

In any case even if the battery is left installed it should last a couple of years. Also, there are quite a few places a spare fob could be well-hidden, e.g., back arm rest or somewhere in the trunk. (Note that the trunk should still lock because the car doesn't "know" the shielded fob is present.)

Either approach should work if you want to carry a spare fob in the car, but until we somehow establish that the fob remains functional for extended periods without a battery, I would go with the shielding approach. Meanwhile, I'm not going to agonize over it, I'm just going to enjoy driving the cah (as we say in Bahstin).

 

Regarding whether or not the fob always putting out a signal....according to the manual, it does: " The Intelligent Key continually consumes battery power as the key receives a signal to communicate with the vehicle. Battery life is about 2 years, although it varies depending on the operating conditions."

I agree we cannot go crazy over this, but the cost of an extra fob ( and some spare batteries) is a small price to pay! So given the intelligent key is a very critical, and a potential weak link - one that you can leave you stranded - I think my armrest is going to contain a little 'emergency key kit', simply containing one working fob (shielded), two spare CR2032 batteries and the attached printout - snippets from the manual)...at least until a technical bulletin comes out!

Now back to enjoying the car! On that note I was driving on the highway yesterday afternoon, big smile on my face, sitting in the lap of luxury, with power to spare, wonderful music surrounding me.. which then automatically lowers itself to a whisper...as the phone rings..and the screen tells me my wife is calling....to which I touch the screen once....have a pleasant hands-free chat with the wife. She then hangs up....I do nothing-...phone disconnects by itself....music comes back on by itself....smile returns by itself! Gotta love it!

TMG

 

Um, yeah, but the, uh, key words are "....as the key receives a signal...". It has a receiver that consumes very little power and is always listening for a signal from the car. If the fob continuously transmitted, even a fraction of a milliwatt, the battery would not last anywhere near two years.

Agreed, the peace of mind is worth it, I am probably going to do the same.

Yup. I've already put 1300 miles on mine in 4 weeks (the car, not my wife....) and still find excuses to drive somewhere.

 

I don't know... Just remember that you are planning on leaving a spare key in your car. This is exactly what thieves are hoping to find when they break into a car. Given the fact that it is pretty easy for thieves to get into these cars, I'm not sure this is a great idea. I'm not so sure your insurance company will cover your stolen car once they find out you left a key in it...

 

Hmmm, this is getting to be a pricey safetynet.

Canadian pricing:

1) Option 1- Via dealer, new fob is $214 (after tax) ; programming is another $108 ; total is $322 CDN

2) Option 2- Find one on bay, say for $80 CDN delivered, plus $108 prgramming is $188 CDN

3) Option 3- FREE - Use the second fob that comes with the car (assumes current key holder is only an occasional driver). Wait for tech bulletin to resolve.

Option 3 is looking good!

TMG

 

Now THAT is an excellent point!

 

I think everyone is loosing sight on what the iKey actually is...it is a RFID, and the battery allows it to transmit a high powered signal. You don't even need the battery to start the car.

Take your spare fob and remove the battery. You will find that you can't unlock the door as the sensor in the car can't read the fobs return signal. Open the door with the metal key and try to start the car. The dash will ask for a key. Put it in the dash slot and there you go...it will start! No fob battery needed. The slot in the dash sends an electromagnetic pulse to the fob...The fob has a rather large antenna winding that picks up this energy and uses it to energize its electronics. It then pulses back a return code.

Only the slot in the dash has the necessary sensitivity to pick this signal up. When the door handle button is pushed a signal is sent and the fob responds with a battery powered (ie powerful) signal that the car can read.

So don't worry about carrying a battery around. The issue here is if the car is loosing its memory of the fob, or the more obvious choice, the fobs internal circuits become damaged and it fails to ever transmit a signal...powered or not.

 

Sounds like we have not yet agreed what the fob is doing....sending or receiving!!

 

bkrider is correct.

The I-Key receives a signal from the car and it responds to this signal with a 2 RF bursts.
The only other time a signal is transmitted is when you press the lock/unlock or other buttons on the key fob.

When you put the key in the slot in the car, the communication is via magnetic coupling - hence you don't need a battery.

 

Regardless of the details about the fob transmitting and/or receiving, we collectively have come up with two methods that appear to allow leaving a key hidden in the car: removing the battery or shielding it with tin (actually, aluminum) foil.

ChemGuy's comment about insurance and leaving a key in the car is indeed a good point. I guess each individual has to make a decision about the risk of being stranded versus the risk of an attempted theft and the thief finding the key and the insurance company not covering it.

Hey, this has been an entertaining and informative thread, and everyone who contributed deserves thanks. This is what a good forum is all about!