Answer for ” What can I do with a Tech 2 scan tool?”:
GM Tech 2 is a diagnostic tool for the most part. It can be used to program out/in certain RPO’s in the BCM and can be used to bleed the ABS brake system without introducing air into the system. The extent to which it can be used to tune a C5 corvette is that if you have a PCM Image that will work for your car you can save the current PCM Image and flash the new one you have onto the PCM. It cannot go in and individually change the tuning tables in the PCM as can say either EFI Live or HP Tuners tuning tools. But then those tools cannot touch the BCM either.
If you do or plan to do a lot of diagnostic work on your car it can be a worthwhile tool. Most of the diagnostic charts in the factory service manual assume the availability of a Tech 2. But you have to learn to use the tool like any other computerized diagnostic tool. It has layers and layers of menues to wade through. But in certain diagnostic situations it can be an invaluable tool because it allows you to turn on and off hundreds of computerized settings to aid in the diagnosis process.
GM intentionally dumbed down the capabilities of the Tech 2 to change things to avoid law suits due to an errant technician that changed engine or emissions settings that could result in engine damage or emissions violations.
Good to know: There are many factories working for Tech 2 production, including the genuine from the dealership and the clone by Chinese.
If you are just looking for a decent Tech 2 for use, a working china clone can be a good option. But you should make sure of the quality!