0390110 JOHNSON ARMATURE

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 does not display "ON". Proceed to Test Step 4.Test Step 3. Check the Status of the Emergency Stop Switch in the OFF Position
Turn the ECS to the OFF/RESET position.
Deactivate the emergency stop switch.
Turn the ECS to the COOLDOWN/STOP position.
Observe the status of the emergency stop switch on Cat ET. Expected Result:The status for the emergency stop switch reads "OFF".Results:
OK - The emergency stop switch is functioning correctly.Repair: The problem may be intermittent. If the problem is intermittent, refer to Troubleshooting, "Inspecting Electrical Connectors".OK
NOT OK - The status for the emergency stop switch does not display "OFF". Proceed to Test Step 4.Test Step 4. Test the ECM
Turn the ECS to the OFF/RESET position.
Disconnect the ECM connector J1/P1.
Remove wire F716-WH(White) from ECM connector P1-23. Install a wire jumper for the wire that was removed.
Reconnect ECM connector J1/P1.
Locate a suitable jumper wire.
Connect the wire jumper in P1-23 to the −Battery.
Turn the ECS to the COOLDOWN/STOP position.
Observe the status for the emergency stop switch on Cat ET.
Remove the wire jumper.
Observe the status for the emergency stop switch on Cat ET.
Turn the ECS to the OFF/RESET position.
Replace all wires. Expected Result:The status for the emergency stop switch displays "OFF" when the jumper is installed. The status for the emergency stop switch displays "ON" when the jumper is removed.Results:
OK - The problem is not with the ECM. Proceed to Test Step 5.
Not OK - The status for the emergency stop switch is incorrect.Repair: Replace the ECM. Refer to Troubleshooting, "Replacing the ECM".Repair CompleteTest Step 5. Check the Switches and the Wiring
Disconnect connector P1 from ECM connector J1/P1.
Activate the emergency stop switch.
Measure the resistance between the −Battery and P1-23. Expected Result:The resistance is greater than 20,000 Ohms.Results:
OK - The resistance is greater than 20,000 Ohms. Proceed to Test Step 6.
Not OK - The resistance is less than 20,000 Ohms. There is a short circuit in the emergency stop switch or in the wiring of the circuit.Repair: Repair the switch or wiring and/or replace the switch or wiring.Repair CompleteTest Step 6. Deactivate the Emergency Stop Switch
Deactivate the emergency stop switch.
Measure the resistance between the −Battery and P1-23. Expected Result:The resistance measures less than 5 Ohms.Results:
OK - The resistance is less than 5 Ohms. The emergency stop switch is OK.Repair: The problem may be intermittent. If the problem is intermittent, refer to Troubleshooting, "Electrical Connectors - Inspect".OK
Not OK - The resistance is greater than 5 Ohms. There is an open circuit in the emergency stop switch or in the wiring of the circuit.Repair: Repair the switch or wiring and/or replace the switch or wiring.Repair Complete