BEARING AS-ROLLER 2500839 - Caterpillar

System Operation Description:The ECM receives two signals from the Start/Stop Switch. A redundant signal is provided to the ECM in order to determine if the Start/Stop Switch is active.The switch is in the STOP position, when both of the signals to the ECM are high.The switch is in the START position when both of the signals to the ECM are low.If two different signals are detected during the powerup, the ECM will determine that one of the signals is incorrect. A diagnostic code will be logged and a diagnostic code will remain active.The engine will continue to run when the ECM detects two different signals. If both of the signals are open, the engine will stop.The Start/Stop Switch can be included in the engine start system. The ECM will begin the engine start sequence, when the contacts close and the engine is not running. Refer to the "Locomotive Manuals" for more information.
Illustration 1 g00850675
Test Step 1. Check for Connector Damage.
Turn the engine control to the OFF position.
Turn the breaker at the battery to the OFF position.
Thoroughly inspect the ECM connectors J1/P1 and J2/P2. 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 pinch points.Expected Result:The connectors and wiring should be free of the following problems: damage, corrosion, abrasion and incorrect attachment.Results:
OK - The connectors and wiring are okay. Proceed to test step 2.
Not OK - The connectors and/or wiring need repair.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Stop.Test Step 2. Check the Status of the Start/Stop Switch on the ET.
Activate one of the Start/Stop Switches. Be sure that none of the other switches have been activated.
Connect the ET to the service tool connector.
Connect the main power.
Monitor the parameter for the switch on the ET.Expected Result:The parameter for the switch should read "ON".Results:
OK - The parameter for the switch reads "ON". Proceed to test step 3.
Not OK - The parameter for the switch does not read "ON". Proceed to test step 4.Test Step 3. Check the Status of the Start/Stop Switch on ET.
Deactivate all the Start/Stop Switches.
Observe the status of the Start/Stop Switch on the Electronic Service Tool.Expected Result:The parameter for the switch should read "OFF".Results:
OK - The parameter for the switch reads "OFF".Repair: The switch is functioning correctly. Stop.
Not OK - The parameter does not display "OFF". Proceed to test step 4.Test Step 4. Check the Start/Stop Switches and the Harness Wiring for an Open Circuit.
Disconnect the main power.
Disconnect the ECM connector J1/P1.
Activate one of the Start/Stop Switches. Be sure that all other switches are not active.
Measure the resistance between P1-29