Does anyone know what the error code er2 means?

Basically when you try to get the positioner to move the dish it comes up with er2 and nothing happens. The box eventually powers itself off on its own. When you try to manuall move by pushing the buttons on the front it doesn't move the box.

Of the problem is the box, and not the actuator, then can I simply apply a 12V DC power supply to the cables and get it to move, and I presume connecting the polarities in reverse, it should move in the opposite direction? (the dish only needs to be moved in position to receive AS5)

As I don't have the box in front of me, are each of the for outputs at the back easily identifable to determine the + and - wires?