SEAL 7Y4630 - Caterpillar

System Operation Description:Use this procedure in order to determine if the circuit for the engine running output is operating properly. There are no diagnostic codes for this circuit.Background InformationThe engine running output is located on J1/P1-13 (Output 4) of the Engine Control Module (ECM) .The engine running output turns on when the engine is running. The engine running output turns off when the engine rpm equals zero. This output can be used to prevent the engagement of the starter while the engine is running. The output can be connected to a relay that disables the starter. The relay is normally closed so cranking can be achieved immediately at powerup. During cranking, the ECM energizes the engine running output once engine rpm reaches 50 rpm below low idle. The output is de-energized if the engine speed falls below the programmed low idle by 100 rpm. The low idle rpm is programmable. The range for low idle is between 700 rpm and 800 rpm.
Illustration 1 g01151036
Engine running output circuit
GMT-560 ApplicationsGMT-560 applications have a programmable parameter "Engine Running Output" that can be programmed to "P1/J1:31". If this parameter is programmed, the engine running output is located on ECM J1/P1-31 (Output 9). This feature allows the ECM to control a relay in order to prevent the starter from being engaged after the engine has started. When the ignition key switch is placed in the ON position, Output 9 is low. The relay is ON and the switch is closed. Current flows to the starter solenoid and this allows the starter to engage. When the engine speed reaches 600 rpm the output will go high. This de-energizes the relay and the switch opens. When the switch is open there is no current flow to the starter solenoid.
Illustration 2 g01151023
Engine Running Output Circuit for GMT-560
Illustration 3 g01151043
Pin locations on ECM connector
(P1-13) Output 4
(P1-31) Output 9 Test Step 1. Inspect Electrical Connectors and Wiring
Thoroughly inspect ECM vehicle harness connector J1/P1, and the firewall bulkhead connector. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Perform a 45 N (10 lb) pull test on terminal 13 in the ECM connector.
Check the ECM connector (allen head screw) for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Check the harness and wiring for abrasion and for pinch points from the sensor 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:
Yes - The wiring is OK. Proceed to Test Step 2.
No - There is a problem with the 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 problem is resolved.STOPTest Step 2. Use Caterpillar Electronic Technician (ET) to Check the Relay
Connect Cat ET to the data link connector.
Turn the ignition key switch to the ON position.
Access the special test "Engine Running Output" on Cat ET. The "Engine