ABS ISUZU TFR SERIES 1997 Workshop Manual

4
System outline
The immobilizer system consists of the four major components, which are DDS-1, Engine Control Module (ECM),
Immobilizer Control Unit (lCU), and transponder.
See page 6 for Gas engine, page 7 for Diesel Engine.
This system can be activated by a correctly programmed transponder and starter switch is set to OFF. This system
can be deactivated by a correctly programmed Transponder Key connected with a correctly programmed ECM and
a correctly programmed immobilizer lCU.
While the system is On
ln case of Gas engine;
The starter cut off relay deactivates function of starter, and the fuel injector power source is deactivated also.
ln case of Diesel engine;
The starter cut off relay deactivates function of starter, and the pump is deactivated also.
What happens without proper transponder operation?
One of the function of transponder is to deactivate or activate starter function. lf the proper transponder is not used,
starter cannot be operated. Because starter cut off relay stays On, cranking engine is not possible.
After the starter cut off relay is deactivated, transponder signal triggers to let immobilizer lCU calculate by
transponder address signal and immobilizer algorithm.
When the result matches with necessary condition, it makes injector power source be activated.
If transponder does not send correct signal, immobilizer lCU and ECM do not activate injector system On. Therefore
the vehicle cannot be operated.
No proper transponder is available, what should be done for the system?
When any proper transponder is not available, a new transponder should be programmed. Up to 5 transponders
can be provided with Tech 2 and by proper procedure. See pages 14-15.
In addition to the absence of proper transponder, it may happen particular secret code to the particular vehicle is
missing. ln this case, the secret code must be provided by your organization (refer to “loss of car pass” on pages
24, 25). Otherwise transponder cannot be programmed in any way.
lf the essential tool Tech 2 for programming and proper software for Tech 2 are not available, there is no permanent
way to fix system. Temporary replace with new ECM, new ECU and new transponder without any secret code can
make the system be deactivated, but it does not last long. Such a replacement does not solve any condition. Even
after replacement, the system is activated automatically in short time and then no operation of the vehicle can be
made in any way.
Tech 2 should be provided in your organization. See page 12.
Caution to the operation
lf an attempt is made to start the engine while the immobilizer system is activated, the CHECK ENGINE indicator
flashes and the engine will not start. See the illustration at the bottom of this page.
Summary of operation
Switch On: Set the ignition and starter switch to OFF.
(Activate)
Switch Off: Set the ignition and starter switch to ON by using the transponder key.
(Deactivate)