355 Security PIN-code

Story: I had bought my 355 with only 1 car key and 1 black fob. Few years ago I purchased the security PIN-code from a local dealership which retrieved it from the factory in Italy. Then I purchased a red fob and a black fob and re-added all 3 to the car following the procedure: red -> black -> black. All 3 key fobs are working with no issues. I never tried the PIN-code until now when a battery in the black fob died. So the car is not taking the security PIN-code which I enter following the procedure of turning the ignition key.

Q: I researched that the key fobs only the transmitters, they don't receive anything. Is it correct? Or do they transmit AND also receive? Also I noticed on this fob reprogramming Youtube video, the guy said: "Here is the new PIN now". He didn't distinguish between the new PIN after the reprogramming is in immobilizer or in the red fob.



There are shops in the US and AU now (which were not exist yet a few years ago when I was ordering the PIN over the dealership) that can retrieve the PIN from either immobilizer (a few coins more) or from the red fob (a few coins less). So to my understanding with all of the above, is the PIN hard-coded to each red fob and when re-registering fobs, is the PIN from the red fob is being written to the car immobilizer thus overwriting the factory-set or whatever PIN was written by the original red fob when the car was made, is it also correct?

 

Thank

Thank you very much. Mark responded right away and confirmed my findings. He also added that if you loose a black fob you would need ANOTHER red fob if you want to add a replacement as the immobilizer is not taking the existing red fob with a matching PIN so you need a red fob with a PIN that is not matching the PIN in the immobilizer or he can program your red fob so it will appear to immobilizer as "new" although it's not.

I sent my red fob to Mark and he retrieved the PIN same day the package was delivered and I tried the PIN and it is good.

Mark said he will add to his video if you buy a used red fob make sure it comes with the corresponded PIN. - Or you will need a someone to retrieve the PIN from the red fob otherwise which was my case. Mark also added that in many cases the PIN from the factory red fob was already overwritten to another red fob so the owners who paid the dealerships to get the PIN from the factory were wasting money so they need to take out and send over the immobilizer to get their PIN. In my case my original PIN was fortunately still a factory so I must used it when re-adding the red and other fobs as you can't put the immobilizer into a learning mode without knowing the current PIN.