WASHER 9R4138 - Caterpillar

System Operation Description:When the local emergency stop switch on the electronic instrument panel is activated, battery power is removed from the engines Electronic Control Module (ECM). Fuel injection signals to the engine stop and the engine then shuts down. A lockout system is incorporated into the circuit which prevents battery power from being restored to the ECM in case the local emergency stop switch is deactivated accidentally. The local emergency stop switch must be deactivated and the Engine Control Switch (ECS) must be turned to the OFF/RESET position in order to restart the engine.When the local emergency stop switch is activated, the emergency stop relay energizes removing voltage to the coils of the primary ECM relay and the secondary ECM relay. The ECM relays will de-energize. This removes the battery voltage to the primary ECM and to the secondary ECM. This will stop the injection signals to the engine. When the emergency stop switch is activated, the emergency stop relay (Lockout) will energize.When the emergency stop switch is deactivated, the emergency stop relay (Lockout) and the emergency stop relay will stay energized through the normally open contacts of the emergency stop relay (Lockout). This prevents the primary ECM relay and the secondary ECM relay from energizing and returning power to the ECM. The ECS must be turned to the OFF/RESET position in order to de-energize the emergency stop relay (Lockout).The circuitry prevents power from being restored to the ECM in case the emergency stop switch is deactivated accidentally.Note: The remote emergency stop switch may affect the operation of the engine.
Illustration 1 g00903948
Note: The Engine Control Switch (ECS) is mounted within an instrument panel that is located on the right side of the engine. The ECS is locked into the AUTO position with a pin. The pin must be removed in order to perform this test. After performing this test, ensure that the ECS is placed in the AUTO position and that the locking pin has been reinstalled.Test Step 1. Check for Connector Damage.
Disconnect main power.
Thoroughly inspect the ECM connectors J1/P1 and J2/P2. Inspect all of the other connectors. Refer to the diagnostic functional test 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:All connectors, pins, and sockets are coupled and/or inserted, and the harness and wiring should be free of corrosion, of abrasion or of pinch points.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 wiring or replace the connectors and/or wiring.STOPTest Step 2. Check the Supply Voltage to the ECM while the Local Emergency