Ignition Key In Signal: Description and Operation

Vehicle key

The vehicle key has a radio interface and a transponder interface. Using the radio interface, the user can actively operate the central locking system, i.e. the vehicle can be locked and unlocked.







A transponder interface is used for the function in the ignition lock. The data is exchanged between the key and the ignition lock via this interface. A battery is not required in the key for this interface. With the optional equipment "Porsche Entry & Drive", the key has an additional radio interface for near-field communication/ detection of approaching of the vehicle (125 kHz). The central locking (open/close function) responds via the normal radio interface (433 MHz).

Communication between the vehicle key and the immobilizer master is encrypted. Vehicle access with the remote control and access with "Porsche Entry & Drive" involve the transfer of 32 bits (4 bytes) of encrypted data. This produces approx. 4 million variants. To start the vehicle, 64 bits (8 bytes, remote control/Porsche Entry & Drive) of encrypted data is transferred for authentication of the key.

Electronic ignition lock

The ignition lock accommodates the vehicle key in the basic variant. The inserted vehicle key can be authenticated via the transponder interface in the ignition lock. To do this, the ignition lock converts the radio information into LIN signals for communication with the immobilizer master.







The ignition lock has three positions for operation:
- OFF
- Ignition (Terminal 15)
- Start engine (Terminal 50)







The vehicle key is reset from the "Start engine" position to the "Ignition" position automatically. The "Ignition" position has a detent so that the position can be uniquely identified at all times. The vehicle key can only be removed in the "OFF" position. For vehicles with Tiptronic transmission, the selector lever must be in the "P" position.

With the optional equipment "Porsche Entry & Drive", the ignition lock contains an operating element. The operating element remains in the ignition lock at all times. In this case, the valid key is authenticated via the radio interface between the vehicle key and immobilizer master.