TUBE AS 3375882 - Caterpillar

Switch 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
Test Step 1. Check the Electrical Connectors and the Wiring
Remove the electrical power from the Electronic Control Module (ECM).
Illustration 2 g01364991
Location of the connectors that are for the switch circuits (typical left side engine view)
(1) Engine interface connector
(2) J1/P1 ECM connectors
Thoroughly inspect connectors (1) and (2). Thoroughly inspect the connections for the suspect switch. Refer to Troubleshooting, "Electrical Connectors - Inspect".
Illustration 3 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 4 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
Perform a 45 N (10 lb) pull test on each of the wires in the circuit for the suspect switch.
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.
Check the harness and wiring for abrasions and for pinch points from the battery to the ECM. 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 wiring and connectors appear to be OK. Proceed to Test Step 2.
Not OK - There is a problem with the wiring and/or a connector.Repair: 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.STOPTest Step 2. Test the Switch for Proper Operation
Disconnect the P1 connector.
Refer to Table 1. Determine the P1 terminal for the suspect switch.
Table 1
Terminals for the Switch Inputs
Name of the Switch Terminal Locations at the J1/P1 ECM Connectors Terminal Locations at the Engine Interface Connector
Maintenance clear switch 22 39
Remote engine stop switch 23 36
Slow vessel mode switch 59 38
Synchronize switch (No.1) 35 34
Synchronize switch (No.2) 44 35
Trip clear switch 40 19
Trolling mode switch 41 37
Connect one lead of a multimeter to the P1 terminal for the suspect switch. Connect the other lead of the multimeter to negative ground. Note: Wiggle the harnesses during the following measurements in order to reveal any intermittent short condition.
Measure the resistance between the P1 terminal for the suspect switch and negative ground.
Activate the switch and measure the resistance again. Expected Result:One resistance measurement indicates an open circuit. The other resistance measurement indicates that a short