The Service functionsof Comfort start with immobilizer.

Replacing control units
The following points must be borne in mind when the CAS or the engine control unit is replaced:
· If a CAS control unit is replaced, it must be ordered using the vehicle identification number (VIN).
Following installation, that starting value must be matched to the engine control unit. This starting value match is performed using the service function (DME/DDE - EWS matching) in the BMW diagnosis system.
· If the engine control unit is replaced, the drive-enable code must be transferred from the CAS to the engine control unit following installation. This operation is also performed using the service function (DME/DDE - EWS matching) in the BMW diagnosis system.
· After the calibration of the EWS and engine control unit, these are mutually linked. It is not possible to replace one of the two control units as a test.

DME/DDE - EWS matching
In the case of a new engine control unit, the service function (DME/DDE - CAS matching) in the BMW diagnosis system is used to read the EWS drive-enable code from the CAS and transfer it into the engine control unit. This means that the engine control unit and the CAS control unit are mutually linked.
If the engine control unit is already linked to the CAS, the service function is used to perform a starting value match. This means that the random code calculation between the CAS and the engine control unit is matched.
A start match is required if there is a variance in the random codes caused by the influence of errors in the two control units.

Locking the remote control/spare key
The service function (Disable remote control/spare key) in the BMW diagnosis system can be used to disable or enable remote controls or spare keys.
It is recommended that a key is disabled if it is lost or stolen. A disabled remote control (or spare key) is not locked in the ignition lock and the engine can therefore not be started. The functions of the radio remote control are also disabled.
A remote control or spare key can only be disabled if the remote control or spare key has been used at least once and it is currently not inserted in the ignition lock.
To run the service function, it is required that a valid and enabled remote control or valid and enabled spare key is detected in the ignition lock.

Activating of a new remote control
Insert the new remote control in the ignition lock and hold in this position until the remote control locks into place. This can take up to ten seconds. After locking, wait another five seconds. The remote control is then ready for use.
If the remote control is a replacement for a lost or defective remote control, the old remote control still has to be blocked using the service function (block/release). To use the Car/Key functions, the service function (Personalization number) has to be run.
 

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