879722 Mercruiser SEAL

Illustration 1 g00637494
Typical schematic
Illustration 2 g01074917
P1 ECM connector (P1-2) Ground level shutdown (NO) (P1-8) Ground level shutdown (NC) (P1-29) Digital returnTest Step 1. Inspect Electrical Connectors and Wiring
Turn the keyswitch to the OFF position.
Thoroughly inspect the ECM connector J1/P1. Inspect all of the other connectors. Refer to 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 for pinch points.Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted. 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 in 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.Verify that the repair eliminates the problem.STOPTest Step 2. Check the Status of the Ground Level Shutdown Switch on Cat ET
Connect Cat ET to the cab service tool connector J42. Start Cat ET.
Turn the keyswitch to the ON position.
Operate the ground level shutdown switch. Observe the status for the ground level shutdown switch on Cat ET.Expected Result:The status of the ground level shutdown switch reads "ON" with the ground level shutdown switch in the SHUTDOWN position. The status of the ground level shutdown switch reads "OFF" when the ground level shutdown switch is in the RUN position.Results:
OK - The status of the ground level shutdown switch reads "ON" with the ground level shutdown switch in the SHUTDOWN position. The status of the ground level shutdown switch reads "OFF" when the ground level shutdown switch is in the RUN position. The ground level shutdown switch is operating normally.Repair: There may be an intermittent problem. If the problem is intermittent, refer to Troubleshooting, "Inspecting Electrical Connectors".STOP
Not OK - The status of the ground level switch does not read "ON" with the ground level shutdown switch in the SHUTDOWN position. The status of the ground level shutdown switch does not read "OFF" when the ground level shutdown switch is in the RUN position. The ground level shutdown switch is not operating normally. Proceed to Test Step 3.Test Step 3. Short the Wires together at the Ground Level Shutdown Switch
Turn the keyswitch to the OFF position.
Record the position of the wiring on the ground level shutdown switch before removing the wires.
Disconnect the wires from the ground level shutdown switch.
Create a short circuit at the ground level shutdown switch between the wire F716-WH and the digital return wire 998-BR. Leave the wire F715-PU open.
Turn the keyswitch to the ON position.
Observe the status of the ground level shutdown switch onCat ET.
Turn the keyswitch to the OFF position.
Remove the short between the wire F716-WH and the wire 998-BR.
Create a short circuit at the ground level shutdown switch between the wire F715-PU and the digital return wire 998-BR.
Turn the keyswitch to the ON position.
Observe the status of the ground level shutdown switch on Cat ET.
Turn the keyswitch to the OFF position.
Remove the wire short.Expected Result:The status of the ground level shutdown switch reads "OFF" when the wire F716-WH and the wire 998-BR are shorted together. The ground level shutdown switch status reads "ON" when the wire F715-PU and the wire 998-BR are shorted together.Results:
OK - The status of the ground level shutdown switch reads "OFF" when the wire F716-WH and the wire 998-BR are shorted together. The ground level shutdown switch status reads "ON" when the wire F715-PU and the wire 998-BR are shorted together. The problem is not with the harness and/or the ECM.Repair: Temporarily connect a new ground level shutdown switch. Verify that the new ground level shutdown switch solves the problem before you permanently install the new ground level shutdown switch.STOP
Not OK - The status of the ground level shutdown switch does not read "OFF" when the wire F716-WH and the wire 998-BR are shorted together. The ground level shutdown switch status does not read "ON" when the wire F715-PU and the wire 998-BR are shorted together. There is a problem in the harness and/or the ECM. Proceed to Test Step 4.Test Step 4. Check for a Short Circuit in the Wiring Harness
Turn the keyswitch to the OFF position.
Remove the ECM connector J1/P1 and disconnect the wires at the ground level shutdown switch.
Measure the resistance between the wire F715-PU at ECM connector P1-2 and every pin in ECM connector P1.
Measure the resistance between the wire F715-PU at the ECM connector P1-2 and engine ground.
Measure the resistance between the wire F716-WH at the ECM connector P1-8 and every pin in ECM connector P1.
Measure the resistance between the wire F716-WH at the ECM connector P1-8 and the engine ground.Expected Result:The resistance is greater than 20,000 Ohms for each measurement.Results:
OK - The resistance is greater than 20,000 Ohms for each measurement. Proceed to Test Step 5.
Not OK - The resistance is less than 20,000 Ohms for one or more of the measurements. There is a short circuit in the harness between the ground level shutdown switch and the ECM.Repair: Repair the connectors or wiring and/or replace the connectors or wiring.STOPTest Step 5. Check for an Open Circuit in the Harness
Create a short circuit at the ground level shutdown switch between the wire F715-PU and the digital return wire 998-BR.
Measure the resistance between the wire F715-PU at the ECM connector P1-2 and the digital return wire 998-BR at the ECM connector P1-29.
Create a short circuit at the ground level shutdown switch between the wire F716-WH and the digital return wire 998-BR.
Measure the resistance between the wire F716-WH at the ECM connector P1-8 and the wire 998-BR at the ECM connector