What scanner does GM use?
There isn't a single scanner GM uses. General Motors relies on a range of diagnostic tools that have evolved over decades, from the classic Tech 2 handheld to modern MDI-based systems running GM's GDS2 software. The exact tool depends on the vehicle year, the type of work (dealer vs. independent shop vs. DIY), and the level of access required for diagnostics or programming.
GM diagnostic tools through the years
Here's a concise timeline of the main diagnostic platforms GM has used, ranging from older handheld devices to current networked systems.
- Tech 2 handheld scanner — a long-running GM diagnostic tool used on many models from the 1990s through the early 2010s.
- Global Diagnostic System (GDS) and Multiplex Diagnostic Interface (MDI) — introduced to diagnose newer GM vehicles via CAN networks and to support more advanced procedures; used with GDS2 and GM service portals.
- MDI-2 and updated GDS2/Techline Connect workflow — the modern hardware/software combination for current GM vehicles, offering faster diagnostics, programming, and cloud-based access.
- TIS2Web and Techline Connect — GM’s service portals that host GDS2, programming routines, and service information for authorized dealers and service providers.
In short, GM’s approach has shifted from stand-alone handheld scanners to integrated diagnostic software running on dedicated hardware, with access often controlled through GM’s dealer networks and authorized service channels.
Current tools for dealers and professional shops
These are the core dealer-facing tools GM currently relies on to diagnose, reprogram, and service vehicles.
- MDI (Multiplexer Diagnostic Interface) and MDI-2 hardware to connect GM vehicles to diagnostic software.
- GDS2 (Global Diagnostic System 2) software for diagnostics, programming, and module updates.
- TIS2Web and Techline Connect portals for access to diagnostics, programming, service information, and updates.
- J2534 pass-through support for compatible independent tools, enabling broader workshop access under GM’s interfaces.
Access to these tools is typically restricted to authorized dealers or licensed independent service providers, often requiring subscriptions, training, and specialized hardware.
Independent and DIY access
There are paths for independent shops and experienced DIYers to work with GM vehicles, but they differ from full dealer access and may be limited to certain capabilities.
- Techline Connect subscriptions and compatible hardware for independent shops seeking GM diagnostics and programming capabilities.
- Use of third-party scan tools that support GM protocols and can interface via standardized tiers like OBD-II or pass-through interfaces.
- For newer GM models requiring programming, access generally relies on authorized channels or approved service networks rather than consumer-grade gear.
Note that while independents and enthusiasts can perform many diagnostics with approved tools, advanced programming and fleet-level diagnostics typically require GM’s official hardware/software or licensed equivalents.
Consumer-friendly scanning options
For everyday maintenance and basic fault finding on GM vehicles, DIYers and consumers can rely on consumer-grade tools. These options cover standard diagnostics but do not provide dealer-level programming capabilities.
- Generic OBD-II scanners — read and clear codes, view live data, and check readiness monitors on most GM vehicles.
- GM-aware third-party scan tools and apps — offer enhanced GM code definitions and data streams, useful for common repairs and monitoring.
- Limitations to expect — these tools typically cannot access GM-specific modules or perform programming without dealership-level access.
If you need advanced diagnostics, module programming, or software updates, you’ll generally need GM’s dealer tools (MDI/MDI-2 with GDS2 via TIS2Web/Techline Connect) or a licensed independent shop with equivalent access.
Summary
GM’s scanner ecosystem is broad and vehicle-era dependent. Modern diagnostics rely on MDI or MDI-2 hardware paired with GDS2 software, accessed through GM’s dealer portals like TIS2Web or Techline Connect. Older GM vehicles used the Tech 2 handheld tool. DIYers can use flexible OBD-II scanners for basic diagnostics, but comprehensive GM-specific diagnostics and programming typically require dealer or authorized independent access. The practical takeaway: the tool you need is dictated by your vehicle’s year, the depth of diagnostics required, and your access rights within GM’s service networks.
