Northstar Engines and System Technical Discussion Discussion, PCM Question II in Cadillac Engine Technical Discussion; Could the PCM for a 1999 Eldorado be put in a 1997 without incident? Same model Eldorado, except H rated ...
nope cant be done the 98 had the advent of theft lock which sent the vin to the cars radio to unlock it i know of that difference in the programming and if it was flashed to suit your car then they would need your vin which would only reset it back down to your unwanted S level. It would be easier to just buy a car with a higher rating then to make one. only a computer form the same car from the same year would work and when i mean same car i mean it to say even so far as a 97 ETC would not work 97 with a 97 Eldor b/c the ETC has magnesteer or stabilitrak *one of the two the base eldo does not have i cannot remember*
Mine has both. Magnasteer was standard on all of them 1997+, Stability was optional, standard on ETC. The Theftlock is a function of the body control module, not the PCM. The PCM only runs the engine and trans. The stability's got its own module, so does Magnasteer. Both of those also talk to the BCM.
I've seen a Stability message on the DIC.
I know the BCM is not compatible, but I think the PCM should be, because there were no changes to the engine/trans.
If this car gets sold, I'm just going to get another 540i Sport, because every Eldorado ETC I've looked at (and I have been looking with replacing mine in mind) has been in poor shape around here, except for the 2000-2002s. If I'm going to spend $20K on an everyday car, I will just spend the extra 5 and get the 540. It's a hell of a lot faster, especially the 6 speed, though I would like the auto more (40K miles/year, lots of city + manual trans = no fun.)
Then why are the Eldorado and ETC part numbers different, yet their wiring the same? They do have a different program. The standard Eldorado is the same # 1996-1999, while the ETC has two numbers - one for Z and one for H but still the same different numbes for the range of years 1996-1999. The H rated 1999 Eldorado is yet a different number. This is why I think that the number includes the programming.
I figure there is no harm to try, the worst is that it will not work.
You see... I can't accept the explanation that it simply won't work without being told why. If you try to tell me they are just incompatible, that's a BS answer, that's not why. Why is it incompatible? Every answer will be disected. I am an engineer (not GM) and do have connections to GM Powertrain (Willow Run, MI and Warren, MI) and my connections say it WILL work, that the PCM handles only the engine and transmission, and that those parts are identical for all three years.