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Gmlan Signals

impala454

By impala454
in Ask A GM Technician

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impala454 Enthusiast

impala454

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I am a software developer by day, and have dabbled around with some OBD-II scanners connected to my computer to get real time data from my truck. I would eventually like to build a complete computer system for the truck which shows real time data on a screen, and logs the data for copying to my home PC. I can currently read all of the generic PID values (here: http://en.wikipedia.org/wiki/OBD-II_PIDs) but the OBD-II bus is slow and I'd like to be able to tap into and read the GMLAN signals, so I can see all of the manufacturer specific data, like odometer, door sensors, temperature/compass data, dash control states, etc. Is anyone here "insider" enough to have a listing of these signal definitions? I'm just a DIYer playing around, I'm not going to be designing some commercial application to sell.

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