Continuity mistake: With his right arm Data is accessing the holodeck circuitry via the manhole while he is holding back a taxi cab with his left arm. Each time the scene switches to viewing Data from the back you see his right hand in the manhole and eventually his left hand appears. All the while you still hear the sound of the taxi cab. Each time the scene shows Data from the front he is holding back the taxi cab with his left hand.
Chicken & Waffles
20th Feb 2013