I'm trying to connect to a 2002 duramax ECU with my mpvi pro. I ASSUMED that GM connected the OBD port straight to the ecu and there are two pins on the ECU labeled "class 2 serial data" so I figured one of those two had to be it... Wrong. HPT connects to it and acts like it loads parameters but everything is gibberish.
Upon further investigation I see that the wiring diagram for the truck shows the obd port connecting directly to the BCM through a different class 2 channel.
Am I screwed and am going to need to buy a BCM and install it as well?
edit-so I tried to read the ECU and it figured out what truck it is from, but failed the checksum.
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