Siemens 5WK4 9045, User Manual, Page: 3 / 9

Siemens VDO Automotive AG SV C BC P2 RF TG
IC: 267T-5WK49046 FCC ID:KR55WK49046
I:\POSTZULA\MB_DC\DesignKey\Original_Doku\Func_Designkey.doc
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General description of the Designkey "Keyless Go"
The Designkey incorporates two main functional features.
1. RF remote control system : activation by button press
2. Keyless go system : activation by an external LF-signal source.
In both activation modes the Designkey answers with the available RF (radio
frequency) interface. For remote control function additionally IR (infra red)
communication is in use.
In regular application the RF receiver is located within the control unit which is
mounted in the car interior. The Designkey RF transmitter antenna is
mechanically integrated in the key head. The RF transmitter is used to
transmit different information by a unidirectional transmission line to the RF
receiver within the control unit.
In regular application the following functions are provided by the Designkey :
- Lock the car
-
Unlock the car
- Unlock the trunk of the car
-
Driver authentication ( Keyless Go )
-
Panic activation ( USA only )
Power supply
The transmitter is provided with 2 Lithium batteries (CR 2025) that both gives
a power supply of +3V.
Buttons
There are three buttons which enable to lock and unlock the doors and to
unlock the trunk and an extra button in case of required panic function (USA
only).
During activation, by button press the microcontroller port is forced to ground
via a “pull-up” within the microcontroller.