Continental Automotive 5WK48089 User Manual

Annex No.5

Functional Description

SIEMENS VDO Automotive AG SV C BC P2 RF TG

FCC ID:KR55WK48089 IC:267T-5WK48089

Functional Description /

User Manual

of the

Siemens VDO

Keyless Vehicle Module

type 5WK4 8079

5WK4 8089

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SIEMENS VDO Automotive AG SV C BC P2 RF TG

FCC ID:KR55WK48089 IC:267T-5WK48089

General functional description

The immobilizer system is equipment which enables comfortable operation of the
vehicle. To be able to operate the vehicle the driver only has to take the key with him.
The vehicle communicates with the key inductively via ferrite- antennas which are
located in the front doors, in the interior of the car and in the bumper. These ferrite
antennas are driven by inductance with a frequency of 125 kHz. By damping the
body sheet-metal of the car, the system's range is kept in defined limits. The range of
the interior antennas of the vehicle is the interior of the car only. This enables the
locating of the key.

The door handles and the trunk lid have been equipped with contacts for the
functions "locking" and "unlocking" the vehicle. Woken up by pulling a door handle
the immobilizer sends a challenge 125 kHz via the corresponding inductive door
antenna to the key. The data transmitted in the process activate the key. The key
sends a code to the radio receiver on the control unit via radio frequency
transmission. The control unit transmits the data to the vehicle's "electronic ignition
starter switch (EZS)”. If this code is assessed as valid in the EZS, the vehicle will be
unlocked.

If a lock command is send to the control module while the vehicle is unlocked, the
EZS and the key interchange a code via the control module and the antennas. If the
key is in the exterior area and the code is valid, the vehicle will be locked.

If it is intended to start the engine of a vehicle, this requires actuation of a start key.
The interior inductive antennas are activated. This is to ensure that the key is inside
the vehicle. If the valid code is emitted by the key, the engine will start. If the code is
invalid, the engine will not start.

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