I would think maybe your manual should help, but on the Original Acela, all 4 pantographs work. Both units should have one pantograph up when running. Which one is up depends on the direction of the train. As you switch directions, one should lower and opposite comes up (this happens on both engines).
Thats how the original worked to be prototypical of the pantograph used depending on direction.
The new version could be different if they changed it. Does your manual tell you?
A call to Lionel might be best bet.
