The software was developed by an individual known as "Terry" and posted in the ScanTool.net forums under the username tmk . In 2003, Terry introduced the tool to the world as a "beta form" and a personal hobby project, openly inviting the community to test it and provide feedback. The original version was a Scantool.zip file, hosted on the now-defunct Geocities platform, a fitting home for one of the internet's early community-driven projects.
Measures the exact alignment offset between the cam and crankshaft. 2. Transmission Tuning and Health gm mode 22 scan tool by terry
The preferred hardware due to its fast processing speeds and STN command set support. The software was developed by an individual known
: Terry wrote a program that ran on simple PC-based interfaces (like the ELM327 ). It was one of the first times a regular car owner could plug in a cheap laptop and see the same high-level data a dealership mechanic saw. Measures the exact alignment offset between the cam
If you’re serious about maintaining, tuning, or reviving a GM vehicle, this tool is one of the most cost-effective performance upgrades you can "install."
To appreciate Terry’s tool, you must first understand Mode $22 (or Mode 22 hex). In the SAE J1979 OBD-II standard, universal diagnostic modes range from Mode 01 (Live Data) to Mode 0A (Permanent Codes). However, automotive manufacturers are allowed to create proprietary modes for deeper factory diagnostics.
Locate the ALDL connector (usually under the driver's side dash). Plug the USB/Serial cable into the computer. Connect the other end to the 12-pin ALDL port.