Anybody know that 1.9d immo system?

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Baja juan
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Joined: 02 Sep 2017, 22:32

Anybody know that 1.9d immo system?

Post by Baja juan »

Hi everybody,

This is my first post on here, i apologize its a technical question but i joined this forum especially to ask this, because it seems NOBODY ANYWHERE remembers or knows anything about this system. If there is any chance anybody in the world still does, i guess the best place to find them is here?

So because i have an obsession with fitting engines where they dont belong (iv done a lot of engine swaps especially in cars and boats for competition use, my daily drivers, etc) i am very familiar with old ecu and immo systems. Because the best diesel engine families were made in the 1990s/early 2000s, i had to learn all about how all this old stuff works.

However when my friend (whos obsessed with veg oil) decided to run a tuned up xud to try to win some races burning cooking oil, i first came accross that immo system.

There is an antenna on the ignition barrel, an immo module, and a slave module/stop solenoid under the armored case on the ip.

I know 90% of people just cut thru the armor to access the stop solenoid, but im not most people. Im
Genuinley curious. Iv got comfortable with most of the obscure old first generation diesel systems (eg lucas epic) that nobody knows about, so when i come across something i dont know about i want to learn about it.

So does anybody know how these systems work? If you lost your key in 1999 and went to a citroen delership, what did they do?

The immo system doesnt even seem to have a place to plug anything into it, so how are they programmed/diagnosed? I doubt the dealership unsoldered the eeprom and reprogrammed it, besides, i believe the part inside the fuel pump has to match too. And its fitted with snap-off bolts.

So, does anybody know anything? Or know anybody who worked in the dealerships at that time?

This forum is the last place on the web i havnt tried yet, so since this is the old french car hq for the world, im hoping somebody will know?

Im determined to add this system to my list of pointless old extinct systems i understand.

Hell Razor5543
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Re: Anybody know that 1.9d immo system?

Post by Hell Razor5543 »

Hello, Baja Juan, and :welc: to the French Car Forum. You do NOT need to apologise for asking a technical question; that is, after all, the main reason this Forum exists.

However, I have to say that I am unable to help much with your query. Don't worry though, as it is highly likely that somebody else who DOES know the answer will come along and help you.

I believe (but I am NOT certain) that the way the immobiliser system works (with programming a key) is along these lines. Assuming you have ONE working key (to allow access to the ECUs) and a Lexia clone (much more than just a diagnostics tool) AND the security code (to prove to the internal security systems you ARE allowed in!) (oh, and the extra keys you want to 'introduce' to the car) you would connect the Lexia to the diagnostics port, turn on the ignition (but not start the engine), select the relevant Lexia menu (I have not had to do this, so I do not know where or which menu this is), tell it how many keys are being programmed in (ALL, including the working key, have to be 'programmed', as any that are not are 'forgotten' by the security systems), enter the security code, and then follow the instructions. I am NOT certain of the exact order of this, but I know that people who have done this will pass on the complete and correct information.

You can normally get the four digit security code from a dealership, normally for a fee and with proof of ownership of the vehicle (although I have been able to get this for my vehicles without this proof, as the staff know I have the vehicle in question).
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Re: Anybody know that 1.9d immo system?

Post by xantia_v6 »

My understanding is that the immobiliser in the fuel pump is more or less the same design as used on earlier cars that had an immobiliser keypad, and requires a 4 digit code to unlock it. The immobiliser chip in the key has a different (longer) code, and (depending on model) the engine ECU or BSI converts the key code to the pump code, using some secret algorithm.
All cars with engine immobilisers have the ability to program (a new) engine ECU or BSI when fitting a new unit, using the key code (which is different again to the 2 mentioned earlier).