Editing Transponder (section)

===Car keys===
Many modern automobiles have keys with transponders hidden inside the plastic head of the key. The user of the car may not even be aware that the transponder is there, because there are no buttons to press. When a key is inserted into the ignition lock cylinder and turned, the car's computer sends a signal to the transponder. Unless the transponder replies with a valid code, the computer will not allow the engine to be started. Transponder keys have no battery; they are energized by the signal itself.<ref>{{Cite web |url=http://carlocksmith.co/7-how-does-transponder-car-key-work.html |title=HOW DOES TRANSPONDER CAR KEY WORK? |date=19 February 2015 |access-date=2 May 2019 |archive-date=2 May 2019 |archive-url=https://web.archive.org/web/20190502135641/http://carlocksmith.co/7-how-does-transponder-car-key-work.html |url-status=dead }}</ref><ref>{{Cite web | url=http://www.rfid-handbook.de/downloads/E2E_chapter03-rfid-handbook.pdf | title=Fundamental Operating Principles | website=www.rfid-handbook.de | access-date=2024-07-26}}</ref>