Ignition key
Transponder
code
Immobilizer
Control
Module
ECM
(1)(2)
(3)(4)
1. Coil antenna
2. Immobilizer Control
Module
3. Engine Control Module
(ECM)
4. Ignition key
8G-2 IMMOBILIZER CONTROL SYSTEM
GENERAL DESCRIPTION
The immobilizer control system designed to prevent vehicle burglar consists of following components.
Engine Control Module (ECM)
Immobilizer Control Module
Ignition key (with built-in transponder)
Coil antenna
Operation of this system is as follows.
(1) Each ignition key has its own code (Transponder code) stored in memory. When the ignition switch is turned
ON, Immobilizer Control Module tries to read the Transponder code through the coil antenna installed to the
steering lock assembly.
(2) Immobilizer Control Module compares the Transponder code read in (1) and that registered in Immobilizer Con-
trol Module and checks if they match.
(3) When it is confirmed that two Transponder codes match each other as described above, Immobilizer Control
Module and ECM check if ECM/Immobilizer Control Module codes registered in them respectively match.
(4) Only when it is confirmed that ECM/Immobilizer Control Module codes match, the engine starts running. If
Transponder codes in Step (2) or ECM/Immobilizer Control Module codes in Step (3) do not match, ECM will
stop operation of the injector and the ignitor (i.e., ignition of spark plug).