automobile remotes

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?

Additionally, anybody know anything about their modulation methods, or FCC regs? i.e. simple on/off key?

--
Rich
Reply to
Rich D
Loading thread data ...

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

Reply to
Jon Elson

So, each manuf'r has its own allocation of ID numbers. And, presumably, its own RF format. Are there FCC regs on that?

Well, no. There's no intern'l body allocating the codes, so in theory, there could be duplication.

Whereas, in the phone network, you dial a number, it's guaranteed to ring exactly one target device.

--
Rich
Reply to
Rich D

For many of the low powered devices the FCC just states what frequency and power level they can use. Just about anything else is up to the designer. Very little FCC regulation.

They are unlicensed devices and often stated that they must accept any interference and not cause any to a licensed service.

Reply to
Ralph Mowery

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.