Gm Mode 22 Scan Tool By: Terry
While "Terry" likely stopped development on this project around 2004, its impact is still felt today. It paved the way for a vibrant community of DIYers who reverse-engineered GM's PIDs, many of which are now compiled in community-maintained lists and CSV files for apps like Torque.
To truly understand the power of this tool, it's essential to grasp what Mode 22 is. In the world of On-Board Diagnostics (OBD-II), different "modes" are used to request various types of data from a vehicle's Electronic Control Unit (ECU). While Mode 01 is the standard for requesting generic real-time data, Mode 22 is a more advanced request mode.
The changed this landscape. Created by an independent developer known in automotive forums as "Terry," this software provides a budget-friendly way to access advanced GM diagnostics. It uses GM's proprietary Mode 22 diagnostic protocol to pull real-time data that standard scanners cannot see. What is GM Mode 22?
Ensure the tool is configured to request data (Read) rather than override controls (Write) unless you are an experienced tuner. Unintended write commands can temporarily disrupt module communication. gm mode 22 scan tool by terry
Terry’s software acts as a translator between your computer or mobile device and the GM vehicle network. 1. Deep Module Scanning
"GM Mode 22 Scan Tool by Terry" is legacy freeware commonly bundled with ELM327 OBD-II interfaces for reading enhanced GM-specific diagnostics. Designed for older operating systems, it provides access to specialized vehicle data parameters not available in standard generic OBD-II modes. For modern GM vehicles, users typically transition to factory-level tools like the OEMTools GM MDI or advanced third-party scanners. Interfuse LLC. Obd2 elm327 v1.5 usb can bus scanner | PDF - Slideshare
Check Device Manager for the correct COM number; close conflicting apps like Torque or ScanMaster. Vehicle key is off or the adapter is poorly seated. While "Terry" likely stopped development on this project
Before OBD-II became standard in 1996, GM used a proprietary data protocol called . Within that protocol, "Mode 22" refers to a specific command that requests real-time data parameters from the ECU (Engine Control Unit).
In the world of automotive electronics, some of the best tools come from independent developers who are frustrated by the limitations of commercial products. "Terry" (often associated with specialized software interfaces and hardware loops for older GM platforms) developed this tool to provide a lightweight, lightning-fast way to pull proprietary data without the overhead of a massive "all-in-one" scanner. Key Features of the GM Mode 22 Scan Tool
Disclaimer: OBD diagnostics require care. Always ensure your vehicle is parked safely when running diagnostics. In the world of On-Board Diagnostics (OBD-II), different
To use Terry’s Mode 22 tool, you need a few simple components:
Standard scanners only talk to the Engine Control Module (ECM). Terry's tool scans the entire vehicle network. It pulls data from Transmission Control Modules (TCM), Body Control Modules (BCM), Electronic Brake Control Modules (EBCM), and Airbag modules. 2. Enhanced PID Reading
The preferred hardware due to its fast processing speeds and STN command set support.
The GM Mode 22 scan tool is a highly advanced diagnostic tool that offers a wide range of features and functions. Some of the key capabilities of the tool include:
The GM Mode 22 scan tool has various applications in the automotive industry, including: