BMW X3 Service & Repair Manual: Emc screws

(EMC = Electro-Magnetic Compatibility)

1. Purpose:

• EMC SCREWS are used in the Bonding/Riveting repair method to re-establish bonding transition.
• They assume the function of welded joints, which ensure transition to ground between the individual components.
• The punch or blind rivets used in the repair do not guarantee permanent bonding transition between the individual components!
• The EMC screws ensure the operational reliability and safety of the electrical/electronic components following repairs!

2. Procedure, aluminum front end:

• Each welded joint which is opened must be replaced by at least 2 EMC screws.
• Position the 2 screws on the flange on which the weld seam has been separated. In the event of partial replacement, position the screws in the area of the component overlap.
• In the case of repairs using partial replacement, the number of EMC screws described in the repair instructions must be fitted.
• Drill holes to a diameter of 4.2 mm and insert screws.
• Seal EMC screws with PU sealing material (risk of corrosion).

3. Procedure, steel body:

• Install the number of EMC screws described in the repair instructions.
• Drill holes to a diameter of 4.2 mm and insert screws.
• Seal EMC screws with PU sealing material (risk of corrosion).