I don"t know why those guys are answering your post since they obviously haven't a clue what your talking about. Anyways Mitchell on demand says hyundai doesn't provide timing information for this engine in the "engine performance section" but in the component locator it says there should be one on the left front engine compartment by the battery.
The grounding terminal disables computer adjustment of the timing so you can set a base timing. this way the computer has a starting point to know how much to advance or retard the timing.