How to use 1997 dodge neon pcm to 2000 dodge neon

The main thing is the PCM/ECU needs to be cross compatible - the pinout and part number have to match up, and the replacement PCM has to be compatible with the other modules like the immobilizer. Once you confirm the part compatibility, then you can swap it in. Once you swap it in, you'll need a bidirectional scan tool with parts pairing support. You shouldn't need to reflash it if they work, but you do need to pair it with the SKIM immobilizer. If it's the same pinout but has a different immobilizer, reprogramming it cannot be avoided. If you have the SKIM system bypassed on the new module it avoids a lot of the programming hassles, but it makes a 25 year old car easier to steal (if it even matters?). Just don't tell your insurance company.

The scan tool needs to meet two requirements: It has to be bidirectional all system and support pairing modules. The Autel ones are able to do it but they cost an arm and a leg to the point I would only recommend buying them if you have something expen$ive to maintain (see: anything Euro) or do your own repairs a lot. If you absolutely have to have that 4 year old $31k E350, you need a good scanner -- comes with the ownership of a Benz to not get burned on repair costs. You can buy this for like $475, but make sure it has module pairing support: https://www.amazon.com/Bidirectional-689... -- if it's lacking, look at something with a fixed update subscription term as it will almost always have it. Any Autel will have it, without a question (but the 3 year subscription is expensive for some -- check the cost of the cards and see if you can avoid the ADAS tax if you do not need it). It may be cheaper to pay a little more to have it pre married to your car's immobilizer.