TERMINAL-CONTACT 2524949 - Caterpillar

Proper welding procedures are necessary in order to avoid damage to the Electronic Control Module (ECM), to sensors, and to associated components. Components that are for the driven equipment should also be considered. Perform welding on the engine according to the following procedure:
Set the engine control to the "STOP" position.
Ensure that the fuel supply to the engine is turned off.
Disconnect the negative terminal from the battery.
Disconnect all electronic components from the wiring harnesses. Disconnect the following components:
Electronic components for the driven equipment
Engine electronic control modules
Fuel actuator
Sensors
Throttle actuator
Do NOT use electrical components (ECM or sensors) or electronic component grounding points for grounding the welder.
When possible, connect the ground clamp directly to the engine component that will be welded. Place the clamp as close as possible to the weld to reduce the possibility of welding current damage to the following components:
Engine bearings
Electrical components
Other engine components
Protect the wiring harnesses from welding debris and spatter.
Use standard welding procedures.