12 00 ... Instructions For Welding Work (Overload Protection Of Control Units)
WARNING: This page is about a different car, the 2007 BMW 550i and 2006 BMW 550i. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
Follow instructions for body repairs.
When performing welding work on installed control units, to avoid any defects in the electronic control units, observe the following steps:
- OBSERVE INSTRUCTIONS FOR DISCONNECTING AND CONNECTING BATTERY .
- Detach terminal of battery negative lead from car battery and second battery if fitted. Cover negative terminal posts.
- If welding is to be performed near the battery/batteries, first remove battery/batteries from vehicle (flying sparks - combustion of explosive gas).
- Fit return clamp on welding unit as close as possible to welding point (maximum distance approx. 1 m).
- Never connect return clamp to ground pin on body which has ground wires attached!