Download  Print this page

System Operation - Mitsubishi Electric IMB223-02 User Manual

Immobilizer ecu
Hide thumbs


2. System operation

(1) Operation start
When the ignition key is turned to the ON position, battery power is supplied to the immobilizer
ECU. And at this time, the engine ECU sends request code to the immobilizer ECU.
(2) Sending to the transponder (Immobilizer ECU to Transponder)
When the request code is received from the engine ECU, the immobilizer ECU sends electromagnetic
wave to the transponder via key ring antenna to supply power and send data to the transponder by means
of electromagnetic coupling.
(3) Sending ID code (Transponder to Immobilizer ECU)
The transponder sends the ID code to the immobilizer ECU via the key ring antenna.
(4) Comparison of ID code
The ID code sent from the transponder is compared with the ID code registered in the immobilizer
(5) Sending condition code (Immobilizer ECU to Engine ECU)
After ID code comparison, the immobilizer ECU sends the condition code to the engine ECU. This
condition code is comprised of the comparison result of ID code (ID code coincident / not coincident,
no ID code receiving).
(6) Receiving condition code
When the engine ECU receives the normal code which contains "ID code coincident", it becomes ready
for start. In the case a code different from this is received, it prohibits engine start.
(7) Engine start
After receiving the normal condition code, the engine can be started by turning the ignition key
to the START position.
(1) Transponder ID code registration to the immobilizer ECU is performed using the MUT. The transponder
key has individual ID code and a maximum of 8 types of codes (8 keys) can be registered to the immobilizer
(2) The immobilizer ECU is provided with a self-diagnosis function, which enables condition checking by
the use of MUT.


Table of Contents