0393781 JOHNSON CARB ASSY., Lower 235 only

Illustration 1 g02210879
Schematic for the emergency stop switchTest Step 1. Inspect the Electrical Connectors and the Wiring
Turn the battery disconnect switch to the OFF position.
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Location of the ECM relay (typical left side engine view)
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Location of the engine interface connector (typical engine view)
Thoroughly inspect the connector for relay (1) and connector (2). Also, thoroughly inspect any other connectors that are associated with the circuit. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
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Terminal locations at the engine interface connector that are associated with the emergency stop switch (4) +Battery (23) Emergency stop
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Terminal locations of the N/O contacts for the emergency stop switch
Illustration 6 g01210818
Terminal locations at the ECM relay that are associated with the emergency stop switch (2) −Battery (5) Emergency stop
Perform a 45 N (10 lb) pull test on each of the wires in the circuit for the emergency stop switch.
Check the torque of the allen head screw for the engine interface connector. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.
Check the harness and the wiring for abrasion and for pinch points from the battery to the ECM relay.Expected Result:All connectors, pins, and sockets are coupled and/or inserted, and the harness and wiring are free of corrosion, of abrasion, and of pinch points.Results:
OK - The connectors and wiring appear to be OK. Proceed to Test Step 2.
Not OK - The connectors and/or wiring are not OK.Repair: Repair the wiring and/or the connectors. Replace parts, if necessary.STOPTest Step 2. Check for Battery Voltage at the Connector for the Emergency Stop Switch
Disconnect the connectors for the emergency stop switch.
Turn the battery disconnect switch to the ON position.
Measure the voltage between the +Battery terminal on the harness side of the connector for the emergency stop switch and the engine ground stud.Expected Result:The correct voltage is 24 3 VDC.Results:
OK - The voltage is 24 3 VDC. The supply voltage is reaching the connector for the emergency stop switch. There may be a problem with the emergency stop switch. Proceed to Test Step 4.
Not OK - The voltage is not 24 3 VDC. The supply voltage is not reaching the connector for the emergency stop switch. There is a problem in the circuit between the emergency stop switch and the battery. Proceed to Test Step 3.Test Step 3. Check the Emergency Stop Switch
Disconnect the engine interface connectors.
Measure the voltage between terminal 4 on the engine harness side of the engine interface connectors and the engine ground stud.Expected Result:The correct voltage is 24 3 VDC.Results:
OK - The voltage is 24 3 VDC.Repair: There is supply voltage at the engine interface connectors, but not at the connector for the emergency stop switch.There is a problem in the harness between the engine interface connectors and the connector for the emergency stop switch. Check the connection at the terminal block. If this connection is OK, the problem may be in a connector or in the harness. Repair the harness and/or the connector. Replace parts, if necessary. Refer to Troubleshooting, "Electrical Connectors - Inspect".STOP
Not OK - The voltage is not 24 3 VDC.Repair: Supply voltage is not reaching the engine interface connector. There is a problem in the circuit from the battery to the engine interface connector. Ensure that the auxiliary circuit breaker is not tripped. If the breaker os OK, repair the harness and/or the connector. Replace parts, if necessary.Refer to Troubleshooting, "Electrical Connectors - Inspect".STOPTest Step 4. Check the Resistance Across the Contacts of the Emergency Stop Switch
Ensure that the emergency stop switch is in the RUN position.
Disconnect the connector at the emergency stop switch.
Measure the resistance between the terminals for the N/O contacts on the switch side of the connector for the emergency stop switch.An open circuit condition is the correct measurement with the emergency stop switch in the RUN position.
Place the emergency stop switch in the STOP position.
Again, measure the resistance between the terminals for the N/O contacts on the switch side of the connector for the emergency stop switch.A short circuit condition is the correct measurement with the emergency stop switch in the STOP position.
Reconnect the connector at the emergency stop switch.Expected Result:The measurements agree with the results that are stated above.Results:
OK - The measurements agree with the results that are stated above. The emergency stop switch is operating correctly. There may be a problem in the harness between the emergency stop switch and the engine interface connector. Reconnect the connectors for the emergency stop switch. Proceed to Test Step 5.
Not OK - The measurements did not agree with the results that are stated above.Repair: There is a problem with the emergency stop switch. Replace the switch. Restore all wiring to the original configuration. Verify that the repair resolves