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Hi I have just inherited an xm M reg from my father who passed on recently. It is now stuck in the garage as neither my brother in law or myself can remember the code, we have both driven the car but not for about 3 yrs. I have looked through all the paper work i can find but no joy. Can anyone tell me if these can be sorted and point me in the right direction. Thanks
Sorry to hear of your situation - it must be terrible for you. sad.gif

The immobiliser number IS REQUIRED as it is effectively a switch in the engine management
ECU that will allow the engine to run. Without it the car cannot start and run. Be careful not
to try any old number as it will lock you out for 10-30 minute period after 3 failed attempts.

The expensive guaranteed route is to find a replacement ECU with a known code either from a car
being broken or borrowed from another Xm but the ECU has to be off an identical engined Xm to
stand any chance of working properly although a manual/automatic gearbox difference may not
cause problems though I've heard it suggested they may be different too!
What specification/engine is the car?

The alternatives are what you have tried already checking through the documentation. Has a
garage/specialist carried out work regularly (even MOT centre) where they may have a record
of the 4 digit code in their paperwork?

Alternatively check where the number may be saved. I've seen them written on the back of the sun
visor, the same number as the replacement parts number on the bonnet release side front door

Other options include 1111 which is on many cars as the original code has never been activated from
this 'garage setting' and a year or birth ie. 1939 etc. If you try this remember 3 strikes and you're
locked out - not 100% certain but switch off the ignition after 2 attempts and try again switching it
back on?

Hope you manage to get somewhere with this. What plans do you have for the car and where are
you located should anyone have a similar ECU to try?

Hi junxa

Sorry about the loss of your father.
For most M reg and earlier cars the garage code was 0001 and this is worth trying as well as the later code of 1111. After that trying random codes will just take too long without much chance of success but as stated could lock the ECU out completely. What model car and where are you as someone on here might offer a loan ECU or even know of a spare with code.
I agree the 0001/1111 combinations are worth a try.

If all else fails, is it possible that Citroen keep a record of engine codes the same as they do with radio codes/ door keys etc.? I might be worth a trip to your local main dealer. Now someone tell me I'm wrong.

Hello Junxa,

Sorry about your Dad,

When I bought my car the code was written on a sticky label stuck to the underside of the glovebox lid. Also the door armrests are cubby holes and I found a luggage label in the driver's one with the code and radio code written on.

Good luck.
citroen doen't have the code. The problem is the owners can change it ..... So Citroen could not possibly have the code. Do you know your fathers bank pin number ? Or any other four digit number ? (he will have used a number he can't forget. eg: The Xantia we just sold was set to my mothers birthdate as we purchased the car from her) Does one button look well used (eg: he has changed it to 9999). I just dissable the annoying things, however to dissable them you first need to know the code!. Who in there right mind would steal a Citroen either way !

Shane L.
Shane wrote " citroen doen't have the code. The problem is the owners can change it "

Yes of course. Another foot in mouth moment by me. sad.gif

Hi All

Some of the recent posts here have reminded me of a car that came to me a few years ago with the 4 immobiliser number keys clearly visible because those keys had been heavily used while the others were untouched. Only 4 numbers to perm then. Might just be worth a close look at the keypad for regular usage before starting to try numbers.
Citroen will sell you a new ECU if a code is lost but there are specialists that can read the contents of the EEPROM in the ECU and pick out the keycode. This is a lot cheaper than a new ECU which may well be near the value of the car.

In the unlikely event that you are unaware of it, the owners manual if present is normally stored inside the fuse box flap, passenger footwell. The codes are often on a card in a plastic sleeve in the manual cover. Also may be written on a page of the manual.

If you wish to try several codes without causing lock out then after 2 attempts switch off the ignition, open and close a door and wait until red light on keypad resumes steady flashing. Turn on ignition and try 2 more codes etc.


Hi All

All good information but word of warning about general trying of codes until the model type is identified.

There are at least 4 versions of the immobiliser code equipment fitted to the XM. These each got progressively more complex adding longer lock outs, extra traps, double coding and the short period plip immobiliser bypass. On the earlier cars the garage code is just a special number (0001 or 1111) that the main code can be set to. On the later Mk2's the immobiliser can present a real problem if you do not get given the main code when you get the car. On these later (post 96ish) cars the main code sits in the background as a trap while the garage code is used. The main and the garage code are now separate stored numbers. The garage code now enables and disables the immobiliser only and can be any 4 digits number other that the users selected main code so if you have not set it up yourself you cannot tell if the car is using the main or garage code. Buy one of these later cars that is running on a random garage code and you may well think you have the previous owners selected main code but you can get totally locked out if you try to change the code or do a battery disconnection as this may even upset the plip bypass.

QUOTE (xmexclusive @ Nov 16 2008, 21:00 PM)
if you have not set it up yourself you cannot tell if the car is using the main or garage code.

Hi John, all,
Sound advice across the range. With the later cars having S and C keys you can test whether the code is the Personal Security Code or a Service (garage) code.
Use the 4 digit number to set Service Mode. Service Mode can only be set using the current Personal Security Code. If the number is a Service Code it will not set up another Service Code.
Try the "unknown" number to set up Service mode if it works it is the Security code if it doesn't it is in Service mode already.

Before I bought mine the keypad was disconnected so as not to require a code entry. I requested it be reconnected so I could check that the recorded code worked, and would set Service Mode.


Hi Robert

Thanks for that, it helps everybody to know.

SC keypad cars had two versions of the immobiliser. Early ones were without plip bypass and later ones with plip bypass. Also all the keypads (even Mk1) are pin compatible and can be interchanged with most of the functionality retained.

Hi All those of you that do not have UK spec cars

There are further non UK versions of the keypad/immobiliser/plip system and the information which is listed above is drawn from my knowlege and documentation for UK cars.

junxa, if none of the above is helpful could you let us know what car you have and where you are as I'm sure someone here will have the parts you need. I can offer an ECU with code from an M reg. 1994 series II CT if that is what you have.

Regards Rodders.
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