What are transponder keys?
The biggest change to the automotive industry in recent times has been the introduction of the built in immobilizer system on all cars manufactured since 1995 (late '94 in some cases). This involves placing a microchip in the head of the key, which is a miniature transmitter and receiver. There is an engine management system in the engine compartment that can recognize the signals transmitted from the key. If the correct signals are not detected the engine will not start. TRANSMITTER+RESPONDER=TRANSPONDER
A chip inside the head of the key transmits a signal to the car when the key is inserted in the ignition. Mechanical element:
key is cut as per traditional key. How does the Microchip work?
An electronic chip with a permanent memory which contains an ELECTRONIC CODE. The transponder has an antenna with which it can interface with an external electronic control device.
Through the antenna the device emits a fixed frequency signal; the transponder receives the signal and then transmits its electronic code, by means of special frequency modulations, to the control device, which is able to process the code.
The transponder has no external input of power supply (passive system); it receives the energy necessary to work from the signal emitted by the external control device (inductive coupling between the control device antenna and that of the transponder). Can all Transponder keys be copied?
A good percentage can now be copied but some brands have a encrypted code which only the car dealers can supply.