LINER 3236758 - Caterpillar

Do not ground the welder to electrical components such as the ECM or sensors. Improper grounding can cause damage to the drive train bearings, hydraulic components, electrical components, and other components.Clamp the ground cable from the welder to the component that will be welded. Place the clamp as close as possible to the weld. This will help reduce the possibility of damage.
Reference locomotive manufacturers instructions for proper welding procedures.
Stop the engine. Remove the electrical power from the ECM.
Disconnect the negative battery cable from the battery. If a battery disconnect switch is installed, open the switch.
Illustration 1 g01143634
Service welding guide (typical diagram)
Connect the welding ground cable as close as possible to the area that will be welded. Components which may be damaged by welding include bearings, hydraulic components, and electrical/electronic components.
Protect the wiring harness from welding debris and from spatter.
Weld the materials by using standard welding methods.