Key number and personalization number

For each vehicle, the Car Access System (CAS) manages two different numbers for the remote control belonging to the vehicle and for each spare key.

Key number
The key number is part of the key detection. As a maximum of 10 keys can exist for one vehicle, the key numbers 1 to 10 are stored in the CAS. The key number cannot be changed.
The key number is transferred to the CAS when the remote control is operated. If the key is in the ignition lock, the key number is read by the CAS directly from the transponder (memory chip) in the key.
In the CAS, each key number is only present once. If required, the key number can be used to block a key in the CAS. To do so, the service function locking and security functions - remote control/key - lock/release is available.

Personalization number
The personalization number is vehicle to call up the Key Memory settings in the vehicle. On unlocking with the remote control, the remote control transmits the personalization number to the CAS. The CAS forwards the number across the data buses to the other control units. On receipt of the personalization number, the individual control units implement the settings set in the Key Memory.
All in all, 4 different Key Memory settings can be coded per control unit. This is why the personalization number can have the values 1 to 4.
On vehicle delivery, the key number and personalization number of the two remote controls delivered are the same. However, the personalization number can be changed using the service function locking and security functions - remote control/key - personalization number.
If other keys are ordered or if a key is replaced, the service function mentioned can be used to enter a personalization number in the range from 1 to 4.
If a new personalization number is assigned, the Key Memory settings for the individual control units must be coded with the CIP program for this number.
 

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