General Motors used several generations of factory diagnostic tools. See GM Tech 2 diagnostic tool for the handheld platform also used with brand-specific software by Saab and Opel/Vauxhall, and GM GDS2 and Techline Connect for later PC-based diagnostic and programming services.
Different vehicle lines overlap in coverage; confirm the exact model, model year, market, software and interface in the applicable service documentation. GM ACDelco technical delivery system.
Earlier tools include Tech 1 and Tech 1A, also used with manufacturer-specific applications on certain Opel/Vauxhall and Suzuki vehicles. See also Holden diagnostics and the model-specific Isuzu and Chevrolet IDSS connection. Opel/Vauxhall workshop manual; Suzuki Tech 1 application manual.