General
The immobilizer system with transponder consists of the IMM control module and a maximum of 8 vehicle keys with integrated transponders or in combination with radio frequency remote control a maximum of 8 remote control keys (keys with folding mechanism).
Communication between vehicle key and IMM control module
The transponder integrated into the key contains a code required to enable the immobilizer. This transponder code is read into the IMM control module when the ignition is switched on and compared with the code stored as valid. If the transponder code read in coincides with the valid stored code in the engine control module, the immobilizer is deactivated and the engine can be started.
Communication with PEC/DSV/MSA engine control modules
The immobilizer is deactivated by a signal from the IMM control module to the engine control modules.
2 versions of the interface to the engine control modules are used:
PWM output with unidirectional communication (vehicles with engine 111)
CAN bus with bidirectional communication (vehicles with engine 601 / 602)