Grounding is fine if all grounds are at the same potential, but they never are exactly the same. If B5 and B6 are a differential input (which I don't know, without the PCM schematic), then connecting B6 directly to the GPS ground terminal could be beneficial.h4x0r wrote: The dakota digital GPS speed sender only has a ground for its own power supply: http://www.dakotadigital.com/pdf/GPS-50-2.pdf
Grounding B6 showed no effect when I tested it.
Joe.