Gm Mode 22 Scan Tool By Terry -

Since Terry’s original software was distributed via BBS (bulletin board systems) and early websites in the 1990s, it lives on through the GM tuning community. You can often find the executable and required cable schematics on:

Many modern users have migrated to TunerPro RT because it supports the same Mode 22 data stream but adds a modern interface, better graphing, and the ability to tune the PROM (EPROM) chips. However, purists still keep a copy of Terry’s original lightweight DOS tool on a bootable USB drive.

It displays sensor readings in real-time, updating several times per second. This allows you to watch how sensors respond to throttle changes, engine load, and temperature shifts—critical for diagnosing intermittent issues.

If you own a 1982–1995 GM vehicle with TPI, TBI, LT1, or Crossfire Injection, the GM Mode 22 Scan Tool by Terry is not a luxury—it is a necessity. Cheap generic readers will lie to you or show blank data. Professional Tech 2 or GDS2 tools will refuse to communicate. Only a dedicated Mode 22 tool bridges the gap.

Is the software perfect? No. You’ll need patience to find a working download and to configure your serial connection. But once it’s running, you will wonder how you ever diagnosed a GM “Check Engine” light without it.

For the price of a USB ALDL cable (around $40-60), you can have dealer-level diagnostics from the early 1990s. Terry may not have a corporation or a tech support line, but his Mode 22 scan tool has kept more vintage GMs on the road than any dealership recall. Download it, connect it, and finally see what your old GM is really thinking.

Disclaimer: The GM Mode 22 Scan Tool by Terry is community-developed software. Always verify compatibility with your specific GM ECM/PCM mask ID and use at your own risk. Incorrect bi-directional commands can damage sensors or actuators. When in doubt, consult factory service manuals for your vehicle.

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. gm mode 22 scan tool by terry

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:

Benefits of Using the GM Mode 22 Scan Tool

There are many benefits to using the GM Mode 22 scan tool, including: Since Terry’s original software was distributed via BBS

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:

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:

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! Many modern users have migrated to TunerPro RT

Once you have the software and cable, follow this guide:

Step 1 – Locate the ALDL Port: Find the 12-pin connector. On most F-bodies and Corvettes, it is under the dash left of the steering column. On trucks, it may be above the gas pedal.

Step 2 – Connect the Cable: Plug your USB ALDL cable into the port. Pins A and B (top two rightmost pins) are typically the ground and data lines, but quality cables auto-detect.

Step 3 – Install Drivers (Windows only): Terry’s original tool was written for Windows 95/98/XP. However, modern versions or community updates run on Windows 10/11 in compatibility mode. Install the FTDI or Prolific drivers for your USB-to-serial adapter.

Step 4 – Launch the Software: Open “GM Mode 22 Scanner by Terry.exe”. Set the correct COM port and baud rate (8192).

Step 5 – Power Cycle: Turn the ignition to ON (engine off for sensor checks) or start the engine. Click “Connect” or “Scan Mode 22”.

Step 6 – Interpret Data: The software will populate fields. Pay special attention to:

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