Technical Ducato Immobilizer + old key

[duncker]

Hi,

The car is Ducato JTD 2,8 (2003). There is a module 8 (Code2 immobox Delphi) inside with serial Eeprom 93LC56B SMD package. The keys are using Megamos Crypto ID48 transponder chips, which are known to be non re-usable ones (locked crypto transponders).

There are lots of key programming equipments and tools (eg. AD900 Pro/AD90 or AD100/T300/MVP/SBB) as well as those blank tranponders/keys in the net.
But are they all just unusable with the situation as follows:

I lost my only pair of keys couple months ago. The car had to be towed to local Fiat service and a new key was ordered from a factory. The key was recoded (with the IMMO Ecu as well) and it's working ok.

Couple weeks ago I found the lost keys. Because of the recoding of immo box, the old key won't start the engine. So now I would like to have a spare key if it still possible to make working?

Inside the old key is the locked transponder with the old data. And therefore the immo box won't "talk" with it. In the transponder there are all the necessary information (but it is "behind the wall" because the tarnsponder is locked).

In this situation all you need to do is to make the immo box understand that there is also a second key "to speak with"? So there in the heart of Immo box is this Eeprom memory (93LC56) which keeps the secret?

Have I understood correct?

Let's presume that I'm right so far?

So if I can get the transponder unlocked (as for example, the AD900 key programmer can do this as far as you can rely on the manual?) and also reprogram the Eeprom data, this old key can work again?

With an proper Eeprom programmer you can read the eeprom dump-file (.bin-file). To make this happen, you should remove the eeprom from the immo box so you need have some electrian skills for this.

After you have this dump-file you can read it with the software (once again the AD900 key programmer includes this kind of software as well). And as far as I know this file contains also the PIN-code which is needed to reprogram transponder chip (if you can get the transponder chip unlocked it is possible to use again?).

So far you have unlocked transponder chip, the eeprom-file and (maybe?) the PIN- code also? What else do you need?

Fiat uses precoded crypto transponders with code2 system? So, I guess these transponders are precoded by a manufactor (using car VIN-number?) so they are unique and therefore those lost keys can't be used again if you lose them?

But in this case you have YOUR OLD KEY (so there is no change what so ever in the chip of the key). All the changes have been made with the eeprom memory of the IMMO ECU?

So I guess this old key CAN BE USED again if you can reprogram the eeprom?

Can this be done with the suitable key programmer (AD900 or maybe SBB)?

Can anybody answer this?

 

[corkman]

The old keys can be coded in along with the new one, when recoding the key memory is cleared probably as a security measure so that lost or stolen keys can't be used. All keys must be present at coding time. As you say the ad900 or sbb should do it. I reckon if you explain to the fiat place you took it they might do it cheap.

 

[duncker]

Hi,

Corkman, I think you are absolutely right.

Recoding procedure will take all keys out of memory as a security measure.

So if the old key can be used again by recoding the immo ecu you can do this with ONBOARD KEY PROGRAMMER like SBB or AD100/T300 etc. So you won't need any Key copy equipment like AD900?

I guess this ONBOARD means cable between EOBD and Key Programmer so that you can "tell" to eeprom which keys you want to work with via ignition barrel?

One thing is still confusing me. If the key transponder chip (in the old key) is locked, does this mean that before anything else it has to be unlocked? Or are these onboard key programmers (SBB/T300 and so on...) able to do the job anyway?

What do this "locked transponder" mean? Locked TP can still communicate with IMMO system but it can not be copied or reprogrammed?
But if you can unlocked it, you can reprogrammed it?

Or does it mean that "locked" is gone forever and the key can't be re-used? So it can't communicate either?

But what about those blank keys which can be found and purchase via net? If you manage to get one, you have virgin transponder as well so you can make a copy of the key by using SBB or T300 quite easily?

Is it so? Or something missing?

Any suggestions?