5031797 JOHNSON *SCREW (5X14mm)

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 Running Output" test will enable the engine running output when the test is active.
Begin the "Engine Running Output" test and listen for the relay to click. You may need to be near the engine in order to hear the click. Expected Result:The relay activates when the special test is enabled.Results:
Yes - The ECM and vehicle components are operating correctly.STOP
No - The ECM and vehicle components are not operating correctly. Proceed to Test Step 3.Test Step 3. Use Cat ET to Check the ECM
Verify that Cat ET is connected to the data link connector.
Turn the ignition key switch to the OFF/RESET position.
Disconnect the ECM vehicle harness connector J1/P1.
Connect a breakout T between ECM connectors J1 and P1.
Connect a voltage test lamp to terminal 13 (Output 4) and terminal 65 (-Battery) of the breakout T. Note: If the vehicle is a GM-560 application, connect the voltage test lamp to terminal 31 (Output 9) and terminal 65 (-Battery) of the breakout T.
Turn the ignition key switch to the ON position.
Access the special test "Engine Running Output" on Cat ET.
Cycle the special test "Engine Running Output" to "Active" and to "Not Active" and watch the voltage test lamp.
Stop the special test. Note: A multimeter cannot be used in place of the voltage test lamp when the ECM outputs are being tested.Expected Result:The voltage test lamp turns on when the test is active. The voltage test lamp turns off when the test is not active.Results:
Yes - The ECM is OK. The problem is in the vehicle wiring. Inspect the vehicle wiring and then repair the vehicle wiring. Otherwise, send the vehicle to the OEM dealer for repair. Verify that the original condition is resolved.STOP
No - There may be a problem with the ECM.Repair: Temporarily connect a test ECM. Use the "Engine Running Output Special Test" onCat ET to check the ECM. If the problem is resolved with the test ECM, install the suspect ECM. If the problem returns with the suspect ECM, replace the ECM. Verify that the repair eliminates the problem.STOP