HUB-IMPELLER 4526698 - Caterpillar

Illustration 1 g00852395
Test Step 1. Check for Connector Damage.
Disconnect main power.
Check the connectors and wiring for the following problems: damage, corrosion, abrasion and incorrect attachment.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 free of problems. Proceed to test step 2.
Not OK - The connectors and wiring are not free of problems.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Stop.Test Step 2. Check the Indicator.
Start the engine.
Shut down the engine.
Observe the Low RPM Indicator on the Caterpillar Electronic Technician (ET).Expected Result:The indicator should activate when the engine shuts down.Results:
OK - The indicator activates when the engine shuts down.Repair: The indicator is OK. Stop.
Not OK - The indicator does not activate when the engine shuts down. Proceed to test step 3.Test Step 3. Check the Circuit.
Close the switch to the +Battery terminal.
Listen for the relay to change.Expected Result:The relay should activate and the lamp should illuminate.Results:
OK - The relay activated and the lamp illuminated. Proceed to test step 4.
Lamp Illuminated - The relay did not activate but the lamp illuminated.Repair: The problem appears to be with the relay. Temporarily install a new relay. If the problem is no longer present, reinstall the old relay. If the problem returns with the old relay, replace the relay. Stop.
Lamp Did Not Illuminate - The relay did not activate and the lamp did not illuminate.Repair: The problem appears to be in the wiring between J2/P2 and the relay. Repair the connectors or wiring and/or replace the connectors or wiring. Stop.Test Step 4. Check the Electronic Control Module (ECM).
Disconnect the main power.
Disconnect J1/P1 and J2/P2.
Insert signal reading probes into P1-5 and P1-4.
Connect the voltage test lamp to the signal reading probes.
The voltage test lamp should illuminate. If the lamp does not illuminate, the lamp is faulty and/or there is a problem with the wiring. Continue this procedure until the lamp illuminates.
Insert one signal reading probe into P1-5. Insert the other signal reading probe into P1-34.
Connect the voltage test lamp to the signal reading probes.
Connect an electronic service tool. Access the override. Enable the override for the Low RPM Relay.
Disable the override.Expected Result:The voltage test lamp should illuminate when the override is enabled. Results:
OK - The voltage test lamp illuminates.Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Stop.
Not OK - The voltage test lamp did not illuminate. The problem is in the wiring between the Electronic Control Module (ECM) and the relay.Repair: Replace the ECM. Perform the diagnostic procedure Troubleshooting, "Replacing the ECM". Stop.