PUMP GP-HYDRAULIC 1G9788 - Caterpillar

circuits may have problems such as faulty wiring, faulty switches, or faulty connectors. Use the following diagnostic procedures in order to diagnose problems with these switch circuits and repair these switch circuits:
Maintenance clear switch
Remote engine stop switch
Slow vessel mode switch
Synchronize switch (No.1)
Synchronize switch (No.2)
Trip clear switch
Trolling mode switchThese switches are normally open or normally closed.
Illustration 1 g01366881
Typical switch inputs and wiring
Illustration 2 g01369114
Terminal locations at the P1 ECM connector that are for the switch circuits
(P1-22) Maintenance clear switch
(P1-23) Remote engine stop switch
(P1-35) Synchronize switch (No.1)
(P1-40) Trip clear switch
(P1-41) Trolling mode switch
(P1-44) Synchronize switch (No.2)
(P1-59) Slow vessel mode switch
Illustration 3 g01369117
Terminals at the engine interface connector that are for the switch circuits
(Terminal 19) Trip clear switch
(Terminal 34) Synchronize switch (No.1)
(Terminal 35) Synchronize switch (No.2)
(Terminal 36) Remote engine stop switch
(Terminal 37) Trolling mode switch
(Terminal 38) Slow vessel mode switch
(Terminal 39) Maintenance clear switch
Illustration 4 g03129657
Location of the connectors that are for the switch circuits (typical left side engine view)
(1) Engine interface connector
(2) J1/P1 ECM connectors
Table 1
Troubleshooting Test Steps Expected Results Results
1. Check the Electrical Connectors and the Wiring
A. Remove the electrical power from the Electronic Control Module (ECM).
B. Thoroughly inspect connectors (1) and (2). Thoroughly inspect the connections for the suspect switch. Refer to Troubleshooting, "Electrical Connectors - Inspect".
C. Perform a 45 N (10 lb) pull test on each of the wires in the circuit for the suspect switch.
D. Check the allen head screw on each ECM connector for the proper torque. Also, check the allen head screw on the customer connector for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.
E. Check the harness and wiring for abrasions and for pinch points from the battery to the ECM.
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.
Result: The wiring and connectors appear to be OK. Proceed to Test Step 2.
Result: There is a problem with the wiring and/or a connector.
Repair the wiring and/or the connector. Replace parts, if necessary. Ensure that all of the seals are properly connected. Verify that the repair eliminates the problem.
2. Test the Switch for Proper Operation
A. Disconnect the P1 connector.
B. Refer to Table 2. Determine the P1 terminal for the suspect switch.
C. Connect one lead of a multimeter to the P1 terminal for the suspect switch. Connect the other lead of the multimeter to negative ground.(1)
D. Measure the resistance between the P1 terminal for the suspect switch and negative ground.
E. Activate the switch and measure the resistance again.
One resistance measurement indicates an open circuit. The other resistance measurement indicates that a short circuit exists.
Result: One resistance measurement indicates an open circuit. The other resistance measurement indicates that a short circuit exists.
The switch is operating correctly. The wiring does not have a short circuit or an open circuit. Operate the engine