Originally Posted By: mechanicx
"Make and store up to 10 rewritable special codes to send to the vehicle computer".
Standard engine codes are regulated by the government and must be the same for all manufacturers. If any of the required codes are not supported correctly the ECM will be subject to recall. Each code must be implemented or emulated in the exact same way so all OBD-II scanners including the Scangauge can show all required OBD-II codes without requiring constant updates.
Special codes for the rest of the engine, bidirectional controls, and all the other
systems are all different between manufacturers, change from year to year, and can be highly model specific. Codes for a ZR6 would likely be very different than codes for a Cavalier. To purchase the code standards and implement everything each year is an expensive task which ensures that the full function scanners are well out of reach of the DIYer. Generally the more advanced the implementation the less manufacturers will be covered so for Snap-on and others to support many manufactures much advanced functionality must be skipped. Some codes require so much work and testing to implement each year that they will only be supported by the manufacturer's official scan tool. Such scanners support only a single manufacturer, are the highest priced, and are updated each year for all the new models so purchase is typically limited to dealerships.
AutoXray, Actron, and Equus do implement a small amount of special functionality with extended engine data, ABS, and transmission special codes but as yet are not trying too hard to eat away at the expensive scanner market.
The X-gauge function of the Scangauge allows it to display read-only special codes. Scangauge has published some common ones. Others will be hard to get if supported at all since they are proprietary and licensed. X-gauge allows the Scangauge to read a few codes that other low cost scanners don't offer.
The Scangauge is not able to actuate bidirectional controls even if you had the codes.
