WARNING: This page is about a different car, the 2005 BMW 645Ci and 2004 BMW 645Ci. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: HUD Inputs/Outputs (Models From 09/2005)
Courtesy of BMW OF NORTH AMERICA, INC.
Fig 2: Legend For HUD Inputs/Outputs (Models From 09/2005)
Courtesy of BMW OF NORTH AMERICA, INC.
Fig 3: HUD System Circuit Diagram (Models From 09/2005)
Courtesy of BMW OF NORTH AMERICA, INC.
Fig 4: Legend For HUD System Circuit Diagram (Models From 09/2005)