Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > sci.electronics.misc > #4974

Re: automobile remotes

Show all headers | View raw

Rich D wrote:

> A question concerning the car remotes; door lock, headlights, etc.
> 
> Each car/handset must be a matched pair, regarding the ID
> and security codes.  Obviously only one car in the parking
> lot ought to respond.
> 
> Are the ID codes determined by each manufacturer, as
> they choose?  Or is there an intern'l body which allocates
> them, such that each is guaranteed unique, just as
> every telephone has a unique number?
Well, they have a chip that is programmed at the factory, probably with a 
sequentially-incremented number.  The car is then trained to accept several 
key's serial numbers.  The all-in-one keys/fobs have two chips, one operated 
by pushbutton with a coin cell for door unlock, and one RF-powered by the 
engine computer through a coil near the ignition lock, for immobilizer.
So, in theory, there should be no two cars anywhere that respond to the same 
code.

Jon

Back to sci.electronics.misc | Previous | Next — Previous in thread | Next in thread | Find similar

Thread

automobile remotes Rich D <rdelaney2001@gmail.com> - 2021-02-16 14:24 -0800
  Re: automobile remotes Jon Elson <elson@pico-systems.com> - 2021-02-18 20:33 -0600
    Re: automobile remotes Rich D <rdelaney2001@gmail.com> - 2021-02-22 12:25 -0800
      Re: automobile remotes Ralph Mowery <rmowery42@charter.net> - 2021-02-22 18:22 -0500

csiph-web