Auto hatch control circuit question

[Mackskibum]

Anyone know how the auto hatch lift knows where in the cycle it is? The Idrive has multiple opening positions you can choose. This implies some type of encoder circuit to position in proper place.

Here's my problem- '10 35d. Worked fine yesterday afternoon. Last night I opened the hatch and it did not lift itself. There was constant pressure in the down position. I had to remove cargo - lifted up on the hatch and the left side actuator broke in half. Removed left actuator. Right side wants to continuously push down. Seems like the index is wrong. Thoughts?

TIA