HOSE AS 3723653 - Caterpillar

Use this procedure to troubleshoot any suspect problems with the emergency stop switch.The emergency stop switch sends a signal to the Electronic Control Module (ECM). The signal is used to determine if the emergency stop switch is active. The emergency stop switch is active when the switch is in the open state and the signal is held high. The emergency stop switch is inactive when the switch is in the closed state and the signal is held low.The ECM monitors the emergency stop signal at all times. The ECM initiates an emergency stop shutdown when the circuit opens, during engine operation.For safety, the ECM will not allow the starting sequence to begin when the emergency stop switch is activated. The engine will not be able to restart until the following conditions are met:
The engine rpm must equal zero.
The emergency stop input must go low.
The ECM has been reset.
Illustration 1 g01057378
Typical schematic
Illustration 2 g01091536
P1 ECM connector
(P1-18) Digital return
(P1-23) Engine shutdown D
(P1-40) "Start/Run/Stop 1" Test Step 1. Inspect Electrical Connectors and Wiring
Turn the ECS to the OFF/RESET position.
Thoroughly inspect the J1/P1 ECM connector and the J2/P2 ECM connector. Thoroughly inspect the connectors for each analog sensor. Refer to Troubleshooting, "Electrical Connectors - Inspect" 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 harness and the wiring for abrasion and for pinch points. Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted, and the harness and wiring are free of corrosion, of abrasion and of pinch points.Results:
OK - The harness and wiring are OK. Proceed to Test Step 2.
Not OK - There is a problem with the connectors and/or wiring.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled.Repair CompleteTest Step 2. Check the Status of the Emergency Stop Switch in the ON Position
Connect the Caterpillar Electronic Technician (ET) to the service tool connector.
Turn the ECS to the COOLDOWN/STOP position.
Activate the emergency stop switch.
Observe the status of the emergency stop switch on Cat ET. Expected Result:The status for the emergency stop switch reads "ON".Results:
OK - The emergency stop switch is working correctly. Proceed to Test Step 3.
Not OK - The status for the emergency stop switch