Necessary preliminary work

WARNING: This page does not describe the selected car, but rather 21 other vehicles, including the 2015 BMW Alpina B7L, 2015 BMW Alpina B7, 2015 BMW 750i, 2015 BMW 750Li, and 2014 BMW Alpina B7L. However, it is still accessible from the selected car via links, so may be relevant.

Read out the fault memory of the DME control unit.
Switch off ignition.
Disconnect BATTERY EARTH LEAD .
Remove RIGHT INTAKE PLENUM .

Picture shows left side. Procedure on right side identical.

Unlock and disconnect plugs (1) on both knock sensors.

Release screws on both knock sensors (2).

Tightening torque 13 62 5AZ .

Remove knock sensors (3).

Fig 1: Identifying Knock Sensors, Connector And Screws

Courtesy of BMW OF NORTH AMERICA, INC.

Installation note:

Clean support face of knock sensors on engine block.

Fig 2: Locating Contact Surface Of Knock Sensors On Engine Block

Courtesy of BMW OF NORTH AMERICA, INC.

NOTE: Check stored fault message.
Delete fault memory.