Using the Mode $22 protocol through this tool unlocks dealer-level data streams. The most common diagnostic uses include: 1. Advanced Engine Metrics
According to legacy OBD-II information, this tool was often bundled alongside other classic diagnostic software like or pyOBD by Donour Sizemore . It provided a targeted approach for GM users who needed more than just a Check Engine Light code. Common Use Cases for the GM Mode 22 Tool
Set the baud rate to match your hardware (typically 115200 bps for CAN-bus vehicles).
: It enables users to view proprietary sensor data that generic tools might miss, such as specific transmission temperatures, ABS data, or body control module (BCM) status. Functionality Comparison
: It is often found in the "downloads" or "free software" sections of OBD diagnostic resource sites gm mode 22 scan tool by terry
With enhanced GM PID files, Torque Pro can act as a modern Mode 22 scanner. ScanMaster ELM: A robust diagnostic program.
You can monitor automatic transmission fluid (ATF) temperature to prevent overheating.
The "GM Mode 22 Scan Tool by Terry" is, for all intents and purposes, an from the early internet era. It was never a product for sale but rather a project shared freely on forums in the spirit of hobbyist development. While its practical use is obsolete, its significance is undeniable:
: Due to its small file size (approx. 1.49Mb), it is easy to install and deploy on older hardware. Limitations ELM327 Software - Interfuse LLC. Using the Mode $22 protocol through this tool
Depending on the version and hardware adapter used, the tool can command specific vehicle components. Users can test fuel pumps, actuate ABS valves for brake bleeding, or reset learned values like Crankshaft Position Variation (CASE) Learn. Hardware and Software Requirements
A high-quality OBD-II adapter is required. High-speed USB interfaces or Bluetooth adapters using the STN1110 or ELM327 (v1.3a or higher) chipsets work best. Cheaper, counterfeit clones often drop data packets during Mode 22 requests.
The Terry GM Mode 22 Scan Tool has become a legendary piece of kit for enthusiasts of late-90s and early-2000s General Motors vehicles. Unlike generic code readers that only provide surface-level data, this specialized tool taps into the specific proprietary "Mode 22" diagnostics used by GM. If you are looking to diagnose a misfire, check real-time sensor data, or perform advanced maintenance on a classic LS-based engine or a 3800 Series V6, this tool is often the most cost-effective bridge between a basic scanner and a professional Tech 2.
To appreciate why Terry's software became a staple on early diagnostic forums, it helps to understand how OBD-II communication is structured. The Society of Automotive Engineers (SAE) establishes specific diagnostic modes, numbered in hexadecimal format: It provided a targeted approach for GM users
Here is everything you need to know about why this tool is a game-changer for GM diagnostics. What is "Mode 22"?
Unlike generic OBD2 scanners that only read "Mode 01" global data, this tool targets , a manufacturer-specific diagnostic mode used by GM to provide access to enhanced data parameters (PIDs) not available through standard protocols.
It bypasses generic restrictions to show exact sensor voltages, raw counts, and fluid temperatures. Key Features of Terry's Tool