GM ignition key readers

[dzorde]

I've seen an article (can't remember where) that talked about a rolling code
facility for automotive key entry. The chip was powered from a coil loop
which received power from another coil around the lock.  It would then Tx a
code to the ECU via the lock coil.  It utilised the rolling code facility.
As to whether any car manufacturers use them ???

Dan     dzorde at geocities.com

>Craig,
>
>          Just resistors. There are 15 possibilities and they range from
>400 ohms to almost 12K ohms.
>
> 
>       Later, rt
>
>
>Craig Pugsley wrote:
>> 
>> Hi there..
>> 
>> A quick question.. (not really efi, but still on car electronics).
>> Do the GM car keys with electronics inside them that the ECU talks to
>> still just use resistors inside the key or have they changed to something
>> more secure (ie something electronic in the key)?
>> 
>> If so, when did they change?
>> 
>> Cheers,
>> Craig.
>> pugsley at trl.oz.au
>> http://www.3rotor.com/rotary/INDEX.HTM
>