Unlock a car over the phone?

Just heard a story in R4 about a women who locked her car keys in the
boot but her husband was unable to unlock the car by using his spare
set over the phone from 60 odd miles away.

It is a Merc which apparently uses both infra-red and "electronic" (I
assume they mean RF) signals. Both Mercedes and the IEEE are a bit
stumped on how this could work, Does the FOAK have any theories?

 

There's a system in the US that does something similar. Called
Star-summat.

 

Whoops! Yes, of course. They are planning on doing a controlled test
this weekend. I was wondering if the kind of phone used was a factor:
Corded landline, analogue cordless, DECT cordless, mobile?

 

Yes. Initially I suspected it being the power of Bullshit earning them a
spot on the Radio/TV etc.

I fail to see how pointing a small RF device at a house phone or
cellphone will magically make the phone or cellphone pickup the RF
signal and transmit it via the fixed or cellular network to another
cellphone and magically squirt RF out of the earpiece.

IR otoh, might be credible, but only if there was a two-way IR link at
both ends and even then... It might work, but the IR link would have to
be totally unfussy about what it's passing.

Actually... wait a minute... she said the boot unlocked but the alarm
went off and I presume only quieted once she'd put the keys in the
ignition...

That points to one system working... probably the IR, and the wireless
end of it was missing as surmised above, so the alarm triggered.
--
Dave
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I demand nothing of you except that you amuse me.

Folding@Home Team UKRM
http://vspx27.stanford.edu/cgi-bin/main.py?qtype=teampage&teamnum=47957

 

Yes, it was caused by something else.
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It's the old "putting-the-key-fob-to-the-temple" trick, innit.

 

On Star, but it's a built-in system. They know where you are and if the
airbag has deployed in an accident.

SWMBO and I were on holiday in a rental car. It was at night and I was
trying to get the rearview mirror to night mode. I didn't see the
buttons for On Star on the bottom of the mirror. We heard a faint voice
asking if we were okay. I said WTF is that to SWMBO? The voice got
louder and said he was the On Star Operator and were we okay. After a
short exchange of why was he calling us, no you pushed the button, no I
was adjusting the mirror, he explained where the button was. It comes
standard in GM vehicles.