Gm Mode 22 Scan Tool By Terry 【ULTIMATE × BUNDLE】

In the mid-2000s, the "GM Mode 22 Scan Tool by Terry" was a small but legendary piece of the early OBD-II hobbyist scene. At the time, General Motors used a proprietary diagnostic method called Mode 22, which allowed for deeper data extraction than the standard OBD-II protocols required by law.

While professional dealership tools like the GM Tech2 cost thousands of dollars, a developer known simply as Terry released a free, lightweight software utility that could "talk" to GM vehicles using this specialized mode. The Story of a DIY Legend

Terry’s tool was born out of the "Wild West" era of car hacking. During this time, enthusiasts were transitioning from the old ALDL systems of the '80s to the more complex computer networks of modern vehicles.

The Problem: Standard scanners could only see "Generic" data like engine RPM or basic trouble codes. To see "Enhanced" data—like individual wheel speeds for ABS or transmission oil temperature—you needed a tool that understood GM's proprietary Mode $22.

Terry's Solution: 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.

The Legacy: Terry's tool became a staple on forums like Scantool.net and early car-tuning communities. It paved the way for modern, affordable bi-directional scanners from brands like Launch and Autel that we use today.

Though largely superseded by modern apps and GDS2 software, "GM Mode 22 Scan Tool by Terry" remains a nostalgic name for anyone who spent their weekends in a garage with a bulky laptop and a dream of fixing their own Chevy or Buick.

In-Depth Review of GM Mode 22 Scan Tool by Terry

The GM Mode 22 scan tool, developed by Terry, is a software-based diagnostic tool designed to interface with General Motors vehicles. This review aims to provide an exhaustive analysis of the tool's capabilities, features, and performance.

Overview

The GM Mode 22 scan tool is a Windows-based application that allows users to connect to a vehicle's onboard computer (ECU) via a compatible OBD-II interface. The tool provides access to various vehicle parameters, enabling users to diagnose and troubleshoot issues, as well as perform advanced functions.

Key Features

Mode 22 Support: The tool supports Mode 22, also known as "Service $22," which allows users to interact with the vehicle's ECU to perform advanced functions, such as reprogramming and configuring vehicle settings.
Multi-Vehicle Support: The GM Mode 22 scan tool supports a wide range of General Motors vehicles, including Chevrolet, Buick, GMC, and Cadillac models.
Parameter Monitoring: The tool provides real-time monitoring of various vehicle parameters, such as engine speed, coolant temperature, and transmission performance.
Trouble Code Reading: Users can read and clear diagnostic trouble codes (DTCs), allowing for efficient diagnosis and repair of issues.
Advanced Functions: The tool offers advanced features, including the ability to perform vehicle configuration and reprogramming.

User Interface and Experience

The GM Mode 22 scan tool features a user-friendly interface, with a logical and intuitive layout. The main dashboard provides quick access to essential functions, while the menu system allows users to navigate to more advanced features.

Connection Process: The tool's connection process is straightforward, with clear instructions provided for connecting to the vehicle's ECU.
Data Display: The tool displays data in a clear and concise manner, making it easy to interpret and analyze.

Performance and Compatibility

The GM Mode 22 scan tool performed well during testing, with reliable connections and accurate data readings.

Vehicle Compatibility: The tool supports a wide range of General Motors vehicles, including newer models with more advanced ECUs.
Stability and Reliability: The tool demonstrated stability and reliability during testing, with minimal crashes or errors.

Comparison to Other Scan Tools

The GM Mode 22 scan tool stands out from other scan tools on the market due to its:

Cost-Effectiveness: The tool offers advanced features at a competitive price point, making it an attractive option for DIYers and professionals.
Specialized Features: The tool's support for Mode 22 and advanced functions sets it apart from more basic scan tools.

Conclusion

The GM Mode 22 scan tool by Terry is a powerful and versatile diagnostic tool designed for General Motors vehicles. Its advanced features, user-friendly interface, and reliable performance make it an excellent choice for DIYers and professionals.

Rating: 4.5/5

Recommendation:

The GM Mode 22 scan tool is recommended for:

DIYers and enthusiasts looking for a cost-effective, advanced diagnostic tool
Professional mechanics and technicians working on General Motors vehicles
Anyone seeking a reliable and feature-rich scan tool for troubleshooting and repairing vehicle issues

Limitations:

The tool requires a compatible OBD-II interface and Windows-based computer
Some advanced features may require additional hardware or software

Future Development:

The developer, Terry, has expressed plans to continue updating and improving the GM Mode 22 scan tool. Future updates may include:

Expanded vehicle support
Additional advanced features
Improved user interface and experience

Overall, the GM Mode 22 scan tool by Terry is a valuable resource for anyone working on General Motors vehicles. Its advanced features and reliable performance make it a worthwhile investment for DIYers and professionals alike.

The GM Mode 22 Scan Tool by Terry is a legacy, free software utility designed to access manufacturer-specific diagnostic data (Mode 22h PIDs) on older General Motors vehicles. It operates with ELM-based OBD-II interfaces to monitor ECU and TCM parameters, though it lacks support for modern CAN FD protocols and is strictly limited to data retrieval. For a list of free OBD-II software options, including this tool, see Interfuse LLC. OBD-II free software - OBDTester

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.

The core appeal of Terry’s tool is its ability to access PID (Parameter ID) data that most budget scanners simply cannot see. Mode 22 is a specific request mode used by GM controllers to broadcast high-speed, live data. While a standard OBD-II scanner might show you a generic oxygen sensor reading, Terry’s setup allows you to monitor individual cylinder misfire counts, transmission line pressure, and torque converter slip in real-time. This level of granularity is essential for tracking down intermittent issues that don’t always trigger a Check Engine Light.

Setting up the scan tool typically requires a compatible interface cable and a laptop running the specific software developed and refined by the community. It is favored by the DIY crowd because it prioritizes function over form. The interface is lean and designed for performance, ensuring that data lag is minimized—a crucial factor when you are tuning a vehicle or trying to catch a momentary dip in fuel pressure.

One of the standout features often cited by users is the misfire monitor. GM’s Mode 22 data is famous for being incredibly sensitive. By using this tool, a mechanic can see if Cylinder 4 is having a slight "hiccup" even if the engine feels smooth to the touch. This allows for proactive maintenance, like replacing a single failing ignition coil or spark plug wire before it leaves you stranded or damages your catalytic converter.

Furthermore, the tool is a staple for those performing engine swaps. When putting a modern GM drivetrain into an older chassis, communication between the various control modules can be tricky. Terry’s tool helps verify that the PCM is receiving the correct signals from the rest of the vehicle, making it an indispensable part of the "LS swap" toolkit.

In a world where automotive software is increasingly locked behind subscriptions and expensive handheld units, the GM Mode 22 Scan Tool by Terry remains a testament to the power of community-driven diagnostics. It provides professional-grade insights for the price of a few parts, ensuring that older GM vehicles stay on the road and perform at their peak. Whether you are a weekend warrior or a dedicated tuner, having this tool in your garage changes the way you interact with your vehicle's computer.

GM Mode 22 Scan Tool by Terry is a free, legacy diagnostic software utility designed for use with ELM327-based hardware interfaces gm mode 22 scan tool by terry

to access enhanced diagnostic data from General Motors vehicles. Key Features and Capabilities

This tool specializes in proprietary GM diagnostic "Mode 22" requests, which provide deeper insight than standard generic OBD-II modes. Its primary functions include: Enhanced Data Access

: Reads ongoing sensor data and fault codes beyond basic emissions-related info, allowing users to view real-time data while driving. Sensor Monitoring : Displays a variety of parameters including: Engine RPM and Vehicle Speed. Coolant and Intake Air Temperatures. Fuel System Status and Fuel Pressure. Short/Long Term Fuel Trims. Timing Advance and Air Flow Rate. Absolute Throttle Position. Code Management

: Allows users to read and clear diagnostic trouble codes (DTCs) and reset the Check Engine Light (MIL). Technical Details Hardware Requirement

: Typically requires an ELM327 USB or Bluetooth interface to bridge the vehicle's computer and a PC. Software Design

: It was originally distributed as a lightweight, user-friendly program. Installation usually involves simply extracting files to a hard drive folder without a complex installer. Availability

: It is often found in the "downloads" or "free software" sections of OBD diagnostic resource sites

Unlock the Full Potential of Your Vehicle with the GM Mode 22 Scan Tool by Terry

Are you tired of throwing money at your vehicle's problems without really knowing what's going on under the hood? Do you want to take control of your car's maintenance and repairs, but don't know where to start? Look no further than the GM Mode 22 scan tool by Terry, a powerful diagnostic tool that's designed specifically for General Motors vehicles.

In this article, we'll take a closer look at the GM Mode 22 scan tool, what it can do, and how it can help you diagnose and fix problems with your vehicle. We'll also explore the benefits of using this tool, and what sets it apart from other scan tools on the market.

What is the GM Mode 22 Scan Tool?

The GM Mode 22 scan tool is a handheld device that's designed to connect to your vehicle's OBD-II port, allowing you to access a wide range of diagnostic information and perform various tests. The tool is specifically designed for General Motors vehicles, including cars, trucks, and SUVs.

The GM Mode 22 scan tool is based on the work of Terry, a well-known DIY enthusiast and mechanic who's been developing and refining his own scan tool solutions for years. The tool is designed to be easy to use, even for those with limited technical expertise, and provides a wealth of information and functionality that's not available with standard OBD-II scan tools.

What Can the GM Mode 22 Scan Tool Do?

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:

Mode 22 data streaming: The tool allows you to access and stream data from your vehicle's engine control module (ECM), transmission control module (TCM), and other systems. This data can be used to diagnose problems, monitor system performance, and make adjustments as needed.
Trouble code reading and clearing: The tool can read and clear trouble codes from your vehicle's ECM, TCM, and other systems. This allows you to quickly identify problems and make repairs, and also reset the check engine light.
Live data streaming: The tool provides live data streaming from your vehicle's sensors and systems, allowing you to monitor performance in real-time.
Bi-directional control: The tool offers bi-directional control, allowing you to send commands to your vehicle's systems and monitor the results.
Component testing: The tool allows you to perform component tests, such as testing the fuel pump, ignition system, and other components.

Benefits of Using the GM Mode 22 Scan Tool

There are many benefits to using the GM Mode 22 scan tool, including:

Cost savings: By using the tool to diagnose and repair problems yourself, you can save money on labor costs and avoid expensive trips to the dealership or repair shop.
Increased control: The tool gives you direct access to your vehicle's systems and data, allowing you to take control of maintenance and repairs.
Improved diagnosis: The tool provides a wealth of information and data that can help you diagnose problems more accurately and quickly.
Enhanced performance: By using the tool to monitor and adjust your vehicle's systems, you can optimize performance and improve fuel efficiency.

What Sets the GM Mode 22 Scan Tool Apart?

The GM Mode 22 scan tool is a unique and powerful diagnostic tool that's designed specifically for General Motors vehicles. Here are a few things that set it apart from other scan tools on the market:

Specificity: The tool is designed specifically for GM vehicles, which means it's optimized for the unique systems and protocols used by GM.
Advanced features: The tool offers a wide range of advanced features, including mode 22 data streaming, bi-directional control, and component testing.
Ease of use: The tool is designed to be easy to use, even for those with limited technical expertise.
Support: The tool is supported by a community of DIY enthusiasts and mechanics who share knowledge, tips, and resources.

Conclusion

The GM Mode 22 scan tool by Terry is a powerful diagnostic tool that's designed to help you take control of your vehicle's maintenance and repairs. With its advanced features, ease of use, and specificity for GM vehicles, this tool is a must-have for anyone who wants to get the most out of their vehicle.

Whether you're a DIY enthusiast, a mechanic, or just someone who wants to save money on repairs, the GM Mode 22 scan tool is an essential tool to have in your toolkit. So why wait? Get your GM Mode 22 scan tool today and start unlocking the full potential of your vehicle!

Additional Resources

If you're interested in learning more about the GM Mode 22 scan tool or want to purchase one, here are some additional resources to check out:

Terry's website: Terry's website is a great resource for learning more about the GM Mode 22 scan tool and other DIY projects.
GM Mode 22 scan tool forums: There are several online forums dedicated to the GM Mode 22 scan tool, where you can connect with other users, ask questions, and share knowledge.
YouTube tutorials: There are many YouTube tutorials and videos available that can help you learn how to use the GM Mode 22 scan tool and diagnose problems with your vehicle.

By taking the time to learn about and use the GM Mode 22 scan tool, you can save money, increase your control over your vehicle's maintenance and repairs, and optimize performance. So don't wait – get started today!

The GM Mode 22 Scan Tool, developed by Terry (often associated with the "Scan Tool by Terry" or "STBT" project), represents a significant milestone in the world of DIY automotive diagnostics. While professional-grade scanners often cost thousands of dollars, this tool was designed to provide enthusiasts and home mechanics with deep-level access to General Motors vehicle data using affordable hardware. The Power of Mode 22

In the world of OBD-II diagnostics, most basic scanners rely on "Mode 01" data, which is the federally mandated generic information required for emissions testing. This includes basic engine RPM, coolant temperature, and oxygen sensor readings. However, GM vehicles utilize Mode 22, a proprietary diagnostic mode that allows for "Enhanced Data."

Mode 22 provides access to specific Parameter IDs (PIDs) that generic scanners cannot see. This includes critical transmission data (like fluid temperature and gear slip), individual wheel speed sensors for ABS troubleshooting, fuel trim data for specific engine banks, and oil life monitoring. By targeting Mode 22, Terry’s tool unlocked professional-level insights for the average user. Accessibility and Community Impact

What makes the "Scan Tool by Terry" notable is its focus on accessibility. In an era where automotive software is increasingly locked behind subscriptions and expensive proprietary interfaces, this project offered a way to interface with GM’s complex Electronic Control Units (ECUs) using standard laptops and inexpensive interface cables.

The tool became a staple in online enthusiast communities. It allowed owners of classic GM platforms—such as the LS-based trucks, Corvettes, and late-model Pontiacs—to perform their own tuning, troubleshoot intermittent electrical ghosts, and verify the health of their drivetrains without a trip to the dealership. Technical Simplicity

The genius of the tool lies in its efficiency. Rather than a bloated graphical user interface, the tool focuses on the raw exchange of data. It interprets the hexadecimal responses from the vehicle's computer and translates them into human-readable values. This lightweight approach ensured that the software could run on older hardware, making it a rugged choice for a garage environment where high-end computers might be at risk. Conclusion

The GM Mode 22 Scan Tool by Terry serves as a testament to the power of the automotive hobbyist community. It bridged the gap between expensive professional equipment and the limited functionality of generic code readers. By democratizing access to manufacturer-specific data, it empowered thousands of vehicle owners to better understand, maintain, and enjoy their GM vehicles.

Should we look into the hardware requirements needed to run this software, or

The GM Mode 22 Scan Tool by Terry is a specialized, often free software utility designed for deep-level diagnostics on General Motors vehicles, typically used in conjunction with low-cost ELM327 OBD2 interfaces. Overview of the Tool In the mid-2000s, the "GM Mode 22 Scan

Unlike generic OBD2 scanners that only read "Mode 01" global data, this tool targets Mode 22, a manufacturer-specific diagnostic mode used by GM to provide access to enhanced data parameters (PIDs) not available through standard protocols.

Platform Compatibility: It is frequently bundled with ELM327 USB or Bluetooth diagnostic kits as part of a free software suite.

Target Audience: It is primarily aimed at DIY enthusiasts and older GM vehicle owners who

Key Capability: 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

While "Terry's" tool is a lightweight utility, it sits between basic code readers and professional factory equipment: OBD II Generic PID Diagnosis - MOTOR Information Systems

Unlocking the Power of the GM Mode 22 Scan Tool: A Deep Dive into Terry’s Custom Solution

For GM enthusiasts, DIY mechanics, and LS-swap aficionados, the term "Mode 22" holds a special kind of reverence. While standard OBDII protocols give you the basics—like engine RPM, coolant temp, and those dreaded P0420 codes—they barely scratch the surface of what a General Motors Engine Control Module (ECM) actually knows.

Enter the GM Mode 22 Scan Tool by Terry. This specialized tool has gained a cult following in automotive forums and tuning circles for its ability to bridge the gap between basic consumer scanners and thousand-dollar professional diagnostic suites.

Here is everything you need to know about why this tool is a game-changer for GM diagnostics. What is "Mode 22"?

Before diving into the tool itself, it’s important to understand the protocol. Standard OBDII diagnostics use "Modes" (like Mode 01 for live data and Mode 03 for stored codes). These are federally mandated and universal across all brands.

Mode 22, however, is a proprietary GM diagnostic service. It allows for "Read Data by Identifier" (DID). In plain English: it lets you request specific, high-resolution data parameters that aren't available on standard scanners. We’re talking about granular transmission pressures, individual wheel speed sensor data, injector pulse widths, and knock sensor activity that standard tools often miss or lag on. The Man Behind the Tool: Who is Terry?

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

The reason this specific tool pops up in so many LS-swap and Silverado forums is its focus on utility over fluff.

High Refresh Rates: Standard OBDII data can be "laggy." Terry’s Mode 22 tool optimizes the request-response cycle, giving you near real-time data which is critical for diagnosing intermittent misfires or tuning fuel maps.

Extended Parameter IDs (PIDs): It unlocks access to PIDs like "Oil Pressure" (which many GM trucks don't report over standard OBDII), "Transmission Fluid Temp," and "Desired vs. Actual Idle."

Bi-Directional Light: While primarily a data logger, certain versions of these custom Mode 22 scripts allow for basic "active tests," such as cycling a cooling fan or testing an EVAP solenoid.

Hardware Compatibility: It is designed to work with affordable interfaces (like the OBDLink MX+ or specialized USB-to-OBD cables), making professional-level data accessible for the price of a few tanks of gas. Why You Need It for Tuning and Troubleshooting

If you are running a 4.8, 5.3, or 6.0 Vortec engine, or a classic LS1/LS6, the GM Mode 22 Scan Tool is your best friend for two specific scenarios:

Diagnosing "Ghost" Issues: Ever have a truck that stumbles but doesn't throw a code? Standard scanners might show a "green light," but Mode 22 can show you that your Long Term Fuel Trims are drifting or that a specific sensor is reporting "noise" just outside the standard threshold.

LS Swaps: When you put a modern GM engine into an old C10 or a Jeep, getting the gauges to talk to the computer is a nightmare. Terry’s tool helps verify that the ECU is seeing the correct inputs before you spend hours wiring up physical gauges. How to Get Started

Using the GM Mode 22 Scan Tool usually involves a specific hardware-software combo. Most users pair a laptop or an Android device with a high-quality OBD interface. Unlike "plug-and-play" tools from big-box stores, you may need to load specific PID lists or configuration files provided by Terry to "unlock" the full potential of your specific VIN. Final Verdict

The GM Mode 22 Scan Tool by Terry isn't for the person who just wants to turn off a gas cap light. It is a precision instrument for the "garage scientist." It provides a window into the brain of your GM vehicle that was previously reserved for dealership technicians with Tech2 scanners.

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."

Unlocking Deep Diagnostics: A Guide to the GM Mode 22 Scan Tool by Terry

If you’ve ever tried to dig deeper into your General Motors vehicle’s brain than a standard $20 code reader allows, you’ve likely bumped into the term Mode 22. While most basic scanners only show "Global OBD-II" data (Mode 01), GM uses Mode 22 for proprietary, enhanced diagnostics.

Among the DIY community, one specific utility has been a long-standing recommendation: the GM Mode 22 Scan Tool by Terry. What is GM Mode 22?

Standard OBD-II protocols are designed for emissions testing and basic engine data. However, manufacturers like GM and Ford use Mode 22 (enhanced diagnostics) to transmit more detailed information through the CAN network.

By accessing Mode 22, you can see "hidden" parameters (PIDs) that standard tools often miss, such as: Transmission Temperature Actual Boost Pressure Battery Current and Engine Torque Oil Life and Fuel Pressure

Because these codes are proprietary, they are often guarded by manufacturers or sold for high fees. Terry's scan tool was developed to give enthusiasts a way to request this data without needing expensive dealership equipment like the GM MDI 2. Why Use the "Terry" Version?

The GM Mode 22 Scan Tool by Terry is a lightweight, legacy software utility designed to work with ELM327-based interfaces. Free USB OBDII software - MoneySavingExpert Forum

The GM Mode 22 Scan Tool by Terry is a legacy freeware diagnostic software primarily used with ELM327-based adapters to interface with General Motors vehicles. Its core purpose is to leverage GM-specific Mode 22 diagnostics, which allow access to a deeper range of sensor data than standard OBD-II protocols. Key Features

Mode 22 Support: Specifically designed to request and display General Motors manufacturer-specific PIDs (Parameter IDs) that are not available through standard Mode 01 requests.

Freeware Availability: Distributed as a free software utility for Windows-based PCs, making it a budget-friendly option for DIY enthusiasts.

Live Data Streaming: Allows users to monitor vehicle performance in real-time by reading raw data directly from the ECU. Mode 22 Support : The tool supports Mode

DTC Management: Capable of reading and clearing diagnostic trouble codes (DTCs) to help identify and reset check engine lights.

Hardware Compatibility: Works with standard ELM327 OBD-II interfaces, including USB and Bluetooth variants.

Platform Support: Traditionally compatible with older Windows operating systems such as Windows 98, 2000, and XP. Modern Alternatives for GM Vehicles

For users with newer GM models (2010+), modern tools often provide more comprehensive "dealer-level" capabilities:

Bluetooth V1.5 V2.1 ELM 327 WIFI/WI-FI V1.5 OBDII ... - eBay

You're looking for information on the "GM Mode 22 Scan Tool" by Terry.

What is GM Mode 22?

GM Mode 22, also known as "Mode 22," is a feature in some General Motors (GM) vehicles that allows for advanced scan tool functionality. It's a protocol that enables communication between a scan tool and the vehicle's onboard computer, providing detailed information about the vehicle's systems and allowing for advanced troubleshooting and repair.

The GM Mode 22 Scan Tool by Terry

The GM Mode 22 Scan Tool, created by Terry, is likely a software or hardware tool designed to interface with GM vehicles that support Mode 22. This tool allows users to access and interpret the data provided by the vehicle's onboard computer.

Features and Capabilities

The GM Mode 22 Scan Tool by Terry might offer various features, such as:

Advanced diagnostics: Retrieve detailed information about the vehicle's systems, including trouble codes, sensor data, and actuator tests.
Real-time data monitoring: View real-time data from various sensors and systems, helping to diagnose issues and monitor repairs.
Trouble code scanning: Read and clear trouble codes, including manufacturer-specific codes.
Service procedures: Perform service procedures, such as resetting the engine oil life monitor or programming replacement modules.

Availability and Usage

The GM Mode 22 Scan Tool by Terry might be available as:

Software: A downloadable program for a PC or laptop, requiring a compatible interface cable to connect to the vehicle.
Handheld scan tool: A dedicated device designed specifically for use with GM vehicles.

To use the tool, users typically need to:

Connect the tool to the vehicle's data link connector (DLC).
Launch the software or turn on the handheld tool.
Follow the on-screen instructions to navigate the menu and select the desired functions.

Note: The GM Mode 22 Scan Tool by Terry might require specific hardware or software configurations, and compatibility with certain GM vehicles. If you're interested in using this tool, ensure you have the necessary requirements and follow proper usage guidelines to avoid damaging your vehicle or the tool.

The GM Mode 22 Scan Tool by Terry is a specialized freeware diagnostic utility designed primarily for Windows and legacy mobile platforms. It is frequently bundled as a complementary software option for ELM327-based Bluetooth and USB scan tools. Key Features and Capabilities

While modern professional scanners like the FOXWELL NT510 Elite offer comprehensive bi-directional controls, this tool serves as a lightweight alternative for specific GM diagnostics:

Platform Support: The software is compatible with Windows, OSX, and older mobile operating systems such as PalmOS and Pocket PC.

Enhanced Mode 22 Access: It is designed to utilize the "Mode 22" diagnostic request, a proprietary GM protocol used to retrieve specific data parameters (PIDs) that standard generic OBD-II Mode 01 requests may not cover.

Core Diagnostic Functions: Like most ELM327-compatible software, it allows users to: Read and clear diagnostic trouble codes (DTCs). Monitor real-time engine data and sensor values. Detect specific system pressures and status indicators.

Portability: Due to its small file size (approx. 1.49Mb), it is easy to install and deploy on older hardware. Limitations ELM327 Software - Interfuse LLC.

Here’s a structured, high-quality content outline about the GM Mode 22 Scan Tool by Terry — ideal for a blog post, video script, or forum guide (e.g., for Diesel Place or GM truck forums).

Review: GM Mode 22 Scan Tool by Terry

Summary

The GM Mode 22 Scan Tool by Terry is a compact, budget-friendly OBD2 diagnostic adapter aimed primarily at GM vehicle owners who want quick access to enhanced diagnostic and programming features specific to GM’s Mode 22 data.

What it is

A plug-and-play OBD2 adapter that exposes GM Mode 22 (manufacturer-specific) data streams, plus standard OBD-II PIDs. Marketed for DIYers and independent mechanics who need deeper GM diagnostics without dealer-level pricing.

Key features

Access to GM Mode 22 manufacturer-specific PIDs.
Reads and clears diagnostic trouble codes (DTCs).
Live data streaming for supported parameters.
Basic freeze frame and readiness status.
Compact design that plugs directly into the vehicle OBD port.
Simple companion app/interface (mobile or desktop, depending on bundle).

Pros

Affordability: Lower cost than dealer tools and many professional scanners.
GM-focused: Useful for GM-specific diagnostics that generic OBD2 tools miss.
Ease of use: Simple plug-and-play operation for basic reads and clears.
Portability: Small form factor makes it easy to carry and store.

Cons

Limited functionality vs pro tools: Lacks advanced bidirectional controls, module programming, and some service procedures found in dealer-level or high-end aftermarket tools.
Compatibility gaps: May not support every GM model/year or every Mode 22 PID—check compatibility for your vehicle.
Support and updates: Dependent on the developer (Terry); firmware/app updates may be less frequent than larger brands.
App polish: Interface and documentation can be basic; power users may want more detailed logging/export features.

Who it’s for

DIY GM owners who want deeper diagnostics than basic OBD2 readers provide.
Independent mechanics needing a low-cost, GM-focused troubleshooting tool.
Not ideal as a primary shop tool for heavy-duty diagnostics, programming, or bi-directional service work.

Practical notes

Verify vehicle/year compatibility before purchase—Mode 22 PID support varies by model year and ECU.
Combine with a more full-featured scanner if you need module programming, immobilizer work, or dealer-level services.
Expect a steeper learning curve if you’re unfamiliar with manufacturer-specific PIDs—some research may be required to interpret Mode 22 data.

Bottom line

The GM Mode 22 Scan Tool by Terry is a good value pick for GM owners and small shops wanting targeted, cost-effective access to manufacturer-specific diagnostics. It’s best as a complementary diagnostic tool rather than a complete replacement for professional-level scanners.

Related search suggestions (If you want more info, I can suggest related search terms.)

How It Works

When a user selects a specific vehicle (e.g., a 2015 Chevrolet Silveroado), the feature presents a "Systems Menu" rather than a generic "Module Menu."

Select System: The user selects "HVAC & Climate."
Smart Dashboard Loads: Instead of just showing raw data, the tool loads a custom interface showing:
- Live Data: Blend door positions, A/C pressure, evaporator temp.
- Bi-Directional Controls (The "Smart" Part):
  - A button labeled "Recalibrate Blend Doors" (This sends the specific GM Mode 22 command sequence to re-home the actuators—solving the common "clicking" issue without a scan tool that costs $3,000).
  - A slider to manually move the "Mode Door" to specific percentages (0%, 25%, 50%, 100%) to diagnose broken gears.

Feature Name: "Smart-Actuator Express"

6. How to Use It (Step-by-Step)

Hardware: ELM327 USB or Bluetooth (USB recommended for speed).
Software: Download Terry’s Mode22ScanTool.exe (from Diesel Place or author’s link).
Connect: Plug into OBD-II port, start app, select COM port, click “Connect.”
Select PIDs: Check desired parameters – e.g., “Injector Balance Rate Cyl 1-8.”
Monitor/Log: Watch live data, save logs for analysis.