While not specific to the TCH, Nissan's warning is worth knowing about:

DETROIT (Reuters) - Nissan North America has a warning for customers: placing your electronic key too close to your cellphone could leave you stranded.

The automaker is asking customers driving new models of two of its flagship sedans to keep their car keys and cellphones at least an inch apart to avoid disabling the "intelligent keys."

Cellphones kept near Nissan's I-Keys -- wireless devices designed to allow drivers to enter and start their cars at the push of a button -- can erase the electronic code on the keys, rendering them unable to unlock or start the cars.

The problem has occurred on the 2007 Nissan Altima and Infiniti G35 sedans -- two of their top-selling models, the company said on Thursday.

"We discovered that if the I-Key touches a cellphone, outgoing or incoming calls have the potential to alter the electronic code inside the I-Key," Nissan spokesman Kyle Bazemore said.

"The car won't start and the I-Key cannot be reprogrammed," he added.

The problem has occurred in a "very small percentage" of cars sold, Bazemore said. He also said a new version of the I-Key would be available in the fall.

Bazemore said current owners have been notified of the potential glitch via mail and can get new keys from dealers if they encounter the problem.

http://www.reuters.com/article/techn...ype=RSS&rpc=22

 

The Toyota Camry manual has a similar caveat. Do not keep the smartkey fob and cell phones in close proximity.

 

Honestly, I find this sad and it really shouldn't be a problem. It should have been on a totally separate frequency and the data should not be that easily manipulated. It is only a matter of time before it gets hacked.

 

Huh?

 

Well, let me see. I think we need Stan (or someone else) to explain how the cellphones interfere with the fob. Honestly, the data integrity should not be so easily compromised. ESPECIALLY by such a common device!

 

Soon, we'll all have cell phones that call, take pictures, text message, and start the car. Cool. I can see the replacement for the Razr on the horizon: The Motorola Slym Jym.

 

LOL

 

I imagine it's related to the power level rather than the specific frequency being used. Like any other wave patterns, as the cell signal disperses over distance the power is also dispersed. At short range (< 1inch you get all the power concentrated). That is also why cell phones at close range will induce noise on nearby speakers and telephones.

As far as hacking into a smart key, I would strongly recommend that if strangers are putting their hands in your pockets that you may consider moving your keys to a different pocket.

 

Yep, it's the "inverse square" rule and applies to RF as well as light.

 

Depends on the stranger I guess...