LINER-BEARING 1453774 - Caterpillar

System Operation Description:To reduce resistance in the wiring harness, there are two isolated power connections to the ECM. The connections must be complete in order to ensure proper engine operation. There may always be a constant power supply to the ECM when the locomotive engine is shutdown. In order to shut off the power to the ECM, the main Battery power needs to be disconnected. The engine will begin the start-up when the following conditions exist:
The ECM detects the input voltage at the keyswitch.
The Emergency Stop switch is not activated.
The Start/Stop switch is activated.Note: To isolate the battery from the ECM, use a power supply that produces 24 VDC. This will protect against voltage spikes and ground loops.An Emergency Stop System and a Start/Stop Circuit are provided in the junction box.The customer can install multiple Start/Stop Switches(push button) and Emergency Stop Push buttons. When the Start/Stop Switches are activated the inputs to the ECM from the Start/Stop switches go low.When the Emergency Stop Push button is activated, the Emergency Stop inputs go high. The fuel supply to the injectors will be cut off and the air shutoff relays will be activated.Proper welding procedures are necessary to avoid damage to the electronic control module and associated sensors and components. The guidelines which are listed should be followed when you are welding on any engine or for any application that uses electronic controls. The guidelines for welding follow:
Stop the engine. Put the start switch on the OFF position.
Disconnect the ECM connectors, J1 and J2 from the harness.
Disconnect the negative battery cable at the battery. If a battery disconnect switch is provided, put the switch in the OPEN position. Do not use fuel system components for grounding the welder.
Connect the clamp for the ground cable of the welder directly to the part. Place this clamp as close as possible to the weld in order to reduce the possibility of damage by the welding current. Components which can be easily damaged include bearings, hydraulic components, and electrical components.
Protect any wiring harness from welding debris and spatter.
Use standard welding procedures in order to weld the materials.
Illustration 1 g00848889
Typical schematicTest Step 1. Check for Connector Damage.
Turn the main disconnect switch to the OFF position.
Thoroughly inspect the ECM connectors J1/P1 and J2/P2. Inspect all of the other connectors. Refer to Troubleshooting, "Inspecting Electrical Connectors" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the circuit.
Check the ECM connector (allen head screw) for the proper torque of 6.0 N m (55 lb in).
Check the customer connector (allen head screw) for the proper torque of 2.25 0.25 N m (20 2 lb in).
Check the harness and the wiring for abrasion and pinch points.Expected Result:The connectors and wiring are free of the following problems: damage, abrasion, corrosion and incorrect attachment.Results:
OK - The connectors and wiring are okay. Proceed to test step 2.
Not OK - The connectors and/or wiring need repair.Repair: Repair the connectors and/or