So… What IS a transponder key?

Many customers often ask us, “What is a transponder?”

The term transponder was invented by the U.S. military back in the late 40s and is short for transmitter/responder. The transponder chip has a specific ID that acts somewhat like a bar code. The vehicle’s Engine Control Unit (ECU) has a set of wires that extends to an antenna that is around the ignition. When the key is turned to the ‘on’ position, the antenna transmits a radio frequency that the chip responds to, and it emits the code or value of the transponder chip. If the ECU recognizes the code as a programmed key, the vehicle’s starter is enabled. If the key is not recognized, the vehicle will not start.