BUSHING 8U5944 - Caterpillar

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ECM (3) J1/P1 connectors (4) J2/P2 connectors
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Component locations (5) Coolant flow switch (6) Coolant temperature sensor
Thoroughly inspect connectors (3) and (4). Thoroughly inspect connector (5) for the coolant flow switch. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
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Terminal locations at the P1 ECM connector for the coolant flow switch (P1-26) Coolant flow switch (P1-29) Sensor return
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Terminal locations at the connector for the coolant flow switch (Terminal 1) Switch signal (Terminal 2) Return
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 allen head screw for each of the ECM connectors for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.Expected Result:All connectors, pins, and sockets are completely inserted and coupled. The harness and wiring are free of corrosion, of abrasion, and of pinch points. All connections and grounds are tight and free of corrosion.Results:
OK - The harness and wiring are OK. Proceed to Test Step 3.
Not OK - There is a problem in the connectors and/or 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 repair eliminates the problem.STOPTest Step 3. Use Cat ET to Monitor the Switch Status
Connect Cat ET to the service tool connector.
Restore electrical power to the ECM.
Observe the status for "Engine Coolant Flow" on the Cat ET.
Start the engine.
Observe the status for "Engine Coolant Flow" on the Cat ET.
Remove electrical power from the ECM.Expected Result:Cat ET indicates "No Flow" while the engine is not running. Cat ET indicates "Flow" while the engine is running.Results:
OK - Cat ET indicates "No Flow" while the engine is not running. Cat ET indicates "Flow" while the engine is running.Repair: The switch is operating correctly at this time. There may be an intermittent problem with the switch or the switch circuit. If an intermittent problem is suspected, refer to Troubleshooting, "Electrical Connectors - Inspect".STOP
Not OK - Cat ET does not indicate "No Flow" while the engine is not running. Cat ET does not indicate "Flow" while the engine is running. Cat ET does not indicate the correct status for the coolant flow switch. Proceed to test step 4.Test Step 4. Create a Short at the Connector for the Coolant Flow Switch
Disconnect the connector for the coolant flow switch.
Fabricate a jumper wire that is long enough to create a short at the harness connector for the coolant flow switch. Crimp connector pins to each end of the jumper wire.
Install the jumper wire to the terminals of the harness connector of the coolant level switch.
Restore electrical power to the ECM.
Observe the status of "Engine Coolant Flow" on Cat ET.
Remove electrical power from the ECM. Restore the wiring to the original configuration.Expected Result:The status indicates "Flow" with the jumper wire in place.Results:
OK - The status indicates "Flow" with the jumper wire in place. The