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Here is everything you need to know about why this tool is a game-changer for GM diagnostics. What is "Mode 22"?
For decades, General Motors vehicles (GM, Chevrolet, Buick, Cadillac, Pontiac, Oldsmobile, GMC) have relied on a unique and powerful data stream known as . While generic OBD-II scanners can read basic engine codes and live data on vehicles from 1996 onward, older GM models (primarily 1980–1995) and even some early OBD-II systems speak a different language. Enter the legendary solution: The GM Mode 22 Scan Tool by Terry .
The GM Mode 22 scan tool, developed by Terry, is a specialized diagnostic tool designed for General Motors (GM) vehicles. This report provides an in-depth analysis of the tool's features, functionality, and benefits, as well as its applications in the automotive industry.
Disclaimer: The original author "Terry" (full identity and version lineage vary across forums) released this tool as freeware for personal use. Always verify compatibility with your specific ECM ID before use. gm mode 22 scan tool by terry
The developer, Terry, has expressed plans to continue updating and improving the GM Mode 22 scan tool. Future updates may include:
