803692 Mercury MAIN NOZZLE

The ground level shutdown switch allows the operator to shut down the engine from outside of the cab. When the switch is toggled to the STOP position, the engine shuts down. The ECM remains powered. Return the engine shutdown switch to the RUN position and cycle the electrical power to the ECM before attempting to restart the engine.The status of the engine shutdown switch can be observed using Caterpillar Electronic Technician (ET).
Illustration 1 g02299697
Schematic for the ground level shutdown switch
Table 2
Troubleshooting Test Steps Values Results
1. Inspect the Electrical Connectors and the Wiring
A. Turn the keyswitch to the OFF position.
B. Thoroughly inspect the connectors. Refer to Troubleshooting, "Electrical Connectors-Inspect" for additional information.
C. Perform a 45 N (10 lb) pull test on the connector wires.
D. Check the harness for abrasions and pinch points.
Connectors and Wiring
Result: The connectors and wiring appear to be OK.
Proceed to Test Step 2.
Result: There is a problem with the connectors and/or wiring.
Repair: Repair or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are coupled.
If the problem is not resolved, proceed to Test Step 2.
2. Check the Status of the Shutdown Switch on Cat ET
A. Connect Cat ET to the service tool connector.
B. Turn the keyswitch to the ON position.
C. Monitor the status screen on Cat ET while you operate the shutdown switch. Observe the status for the shutdown switch.
Note: Wait at least 30 seconds for the status of the switch to change.
Shutdown Switch Status
Result: The status of the shutdown switch reads "ON" with the shutdown switch in the STOP position. The status of the shutdown switch reads "OFF" when the shutdown switch is in the RUN position. The shutdown switch is operating normally.
Repair: The circuit for the shutdown switch appears to be operating correctly. There may be an intermittent problem in the harness or in a connector. If an intermittent problem is suspected, refer to Troubleshooting, "Electrical Connectors - Inspect".
If the repair does not resolve the problem, proceed to Test Step 3.
Result: The status of the switch does not read "ON" with the shutdown switch in the STOP position. The status of the shutdown switch does not read "OFF" when the shutdown switch is in the RUN position. There is a problem with the circuit for the shutdown switch. There may be a problem with the ECM.
Proceed to Test Step 3.
3. Short the Terminals at the Harness Connector for the Shutdown Switch
A. Turn the keyswitch to the OFF position.
B. Fabricate a jumper wire that is long enough to short circuit two terminals at the harness connector for the shutdown switch. Crimp connector pins to each end of the jumper wire.
C. Disconnect the harness connector for the shutdown switch.
D. Check the status of the shutdown switch while the circuit is shorted to the RUN position.
1. Install the jumper wire between terminals 1 (ground level shutdown switch (N/C)) and 2 (digital return) at the harness connector for the switch.
2. Turn the keyswitch to the ON position.
3. Observe the status of the shutdown switch using Cat ET.
Note: Wait at least 30 seconds for the status of the switch to change.
The correct status for the shutdown switch is "OFF".
4. Turn the keyswitch to the OFF position.
E. Check the status of the shutdown switch while the circuit is shorted to the STOP position.
1. Install the jumper wire between terminals 2 (digital return) and 3 (ground level shutdown switch (N/O)) at the harness connector for the switch.
2. Turn the keyswitch to the ON position.
3. Observe the status of the shutdown switch using Cat ET.
The correct status for the shutdown switch is "ON".
Shutdown Switch Status
Result: The switch status on Cat ET agrees with the test results.
Repair: There is a problem with the shutdown switch. Replace the shutdown switch. Verify that the new shutdown switch solves the problem.
If the repair does not eliminate the problem, proceed to Test Step 4.
Result: The switch status on Cat ET does not agree with the test results that are stated above. The problem is in the harness between the ECM and the harness connector for the switch. There may be a problem with the ECM.
Proceed to Test Step 4.
4. Short the Terminals for the Shutdown Switch at the ECM
A. Disconnect the J1/P1 ECM connectors.
B. Fabricate three jumper wires that are long enough to short circuit the terminals at the P1 ECM connector. Crimp connector sockets to one end of each of the jumper wires.
C. Remove the wires from terminal locations P1-5, P1-40, and P1-41 at the ECM connector. Install a jumper wire into each of these terminal locations.
D. Check the status of the shutdown switch while the circuit is shorted to the RUN position.
1. Short circuit the ends of the jumper wires that are in terminal locations P1-5 and P1-41 at the ECM connector.
2. Turn the keyswitch to the ON position.
3. Observe the status of the shutdown switch using Cat ET.
The correct status for the shutdown switch is "OFF".
E. Check the status of the shutdown switch while the circuit is shorted to the STOP position.
1. Short circuit the ends of the jumper wires that are in terminal locations P1-5 and P1-40 at the ECM connector.
2. Turn the keyswitch to the ON position.
3. Observe the status of the shutdown switch using Cat ET.
The correct status for the shutdown switch is "ON".
F. Turn the keyswitch to the OFF position.
G. Restore the wiring to the original configuration.
Shutdown Switch Status
Result: The switch status on Cat ET agrees with the test results.
Repair: There is a problem in the harness between the ECM and the harness connector for the shutdown switch. There may be a problem with a connector. Repair the harness and/or the connector. Replace parts, if necessary.
Verify that the repair resolves the original problem.
Result: The switch status on Cat ET does not agree with the test results that are stated above.
Repair: There appears to be a problem with the ECM. Before you consider replacing the ECM, consult the Dealer Solutions Network (DSN) for assistance.