The part that doesn't make sense to me is the separate black wire in the bridge connector at spot number 8. The MB connectors at the seat and on the bridge have orientation pins so they only connect the right way. Look at the attached photo of the interior of the MB connector on the seat. The brown wires on top are at 3 and 7. They both get jumped by the bridge connector. The red wires are at 4 and 8. Any red wires at 2,4, or 6 would get jumped to the common red (hot), but number 8 (bottom right) is fed by the black wire (on the passenger side) and goes to a black wire on the floor. On the driver's side the extra wire on the floor is purple, but if the (missing) driver's side bridge is the same the purple would feed the separate red wire at position 8.
I connected driver's seat while not installed, using the passenger side bridge connector. Even if I don't bother to connect the black wire of the bridge connector at the floor, all power functions on the seat work. So, what is the purpose of the red at number 8 on the seat?
