User's Manual

Title : User manual of IM900 Immobilizer Spec. No. : N/A
Written by : SUNG HUN AHN Rev. No. : Revision A
Date :2007.11.07 Page : 6 / 10
Technical Center Automotive Electronics
4. System Components
4.1 Accessory Key with Integrated Transponder
4.1.1 Transponder Mounting
The transponder is placed invisible inside the Accessory key. A second Accessory key with integrated
transponder on the bunch doesn’t affect the reading process.
4.1.2 Transponder Function
The transponder is a read/write RF transponder. The transponder contains an implementation of a crypto-
algorithm with user configurable secret-key contained in EEPROM. It also provides a unique device
identification that can never be modified
4.1.3 Transponder Specification
*. Electrical data
- Nominal resonance frequency RF = 125kHz +/- 3kHz
- Bit Period 256us at RF = 125kHz
- Bitcoding Manchester
- Modulation AM