Just curious if anyone knows.
My car has had 3 of them. The first two went bad because of water ingress. (Fixed now).....all three have had totally different numbers.

Because of my bad experience and also because I like to have back ups, I have picked up additional XJS ECU's "just in case". All of these have different numbers, and they all seemed to work fine on my car when I briefly tried them out, even the California unit.

Can anyone confirm that they are all interchangeable? (Even the CA ones?)

 

I have had two 96s. I kept the ecu on the one that the insurance company took. The numbers between the two were totally different as well. (Don't have the two numbers with me)

When I was experiencing the hgh idle, neither ECU made a difference. (for whatever that tidbit of info is worth)

 

I have a feeling that all of them-even the California ones-are interchangeable.


It would be nice to know for sure though

 

Why would they be any different?

JDHT doesn't seem to separate a California ECU, even though they typically separate out German, Japanese, even parts from Saudi Arabia when necessary. Ive never seen any part on eBay identified as a California part.

I believe California mandates special emissions requirements, which I believe the OEM cats met. The ECUs should be no different across all 50 states.