12 00 ... Instructions For Welding Work (Overload Protection Of Control Units)

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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. See 12 00 ... 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!