For those not in the know, often auto manufacturers will extend exiting protocol like ISO 9141, J1850 PWM, Keyword 2000, CAN, and VPW.
Tech2 is a hand scanner based on GMLAN which is a set of high level protocols for diagnosing ECU systems on supported vehicles. There are more than 20 different commands for reading,writing, and clearing information inside an ECU. GMLAN is a combination of GM2190 and Keyword 2000 diagnostics. All functions are defined in GMW 3110. GMLAN uses functions from ISO15765-2 (USDT Messaging) and supports OBD CAN, legislated by J1979 Requirement.
GMLAN has been extended with additional requirements and is often referred to as GM Global A. Global A includes many types of networks and protocols.
As for tools/scanner, Innova is the largest American company for these type of tools. Top line models with Full feature set are 5160, 5160RS (new model), and 7111 (tablet). I've seen them 2nd hand for $150 to $400.
I looked at Launch brand (linked above) but wanted something HQ here.
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