0380874 JOHNSON HOUSING,Starter

Table 1
Diagnostic Codes Table    
Code and Description    Conditions which Generate this Code    System Response    
485-5 Engine Fan Rev Solenoid open circuit     The Electronic Control Module (ECM) detects a low current in the circuit for the engine fan reversing solenoid..     The engine fan reversing solenoid will not function. The code is logged.    
485-6 Engine Fan Rev Solenoid short to ground     The Electronic Control Module (ECM) detects a high current in the circuit for the engine fan reversing solenoid.    The purpose of a reversing fan is to clean debris from the radiator. This is done by temporarily reversing the direction of the air flow through the radiator fins in order to purge the radiator fins. For some applications, the reversing fan is used to heat the engine compartment during cold weather operation.In the automatic mode, the fan reversing solenoid is controlled by the Electronic Control Module (ECM). The ECM will automatically reverse the direction of the fan's rotation. The ECM will use a preset time interval to cycle the fan reversing solenoid. The operator can manually reverse the fan's rotation by pressing the engine fan reverse switch. While the momentary switch is depressed, the direction of the fan's rotation will reverse. Once the switch is allowed to reset, the fan returns to normal operation and control of the fan will return to the automatic operation.Note: For Pipelayer applications, momentarily pressing the engine fan reverse switch will place the fan's rotation in reverse. The fan will remain in reverse until a specified engine coolant temperature is reached.
Illustration 1 g02000083
Schematic for the fan reversing solenoidTest Step 1. Inspect the Electrical Connectors and the Wiring
Turn the keyswitch to the OFF position.
Turn the battery disconnect switch to the OFF position.
Illustration 2 g01186024
Location of the J1/P1 ECM connectors (typical left side engine view)
Thoroughly inspect the J1/P1 ECM connectors. Also, thoroughly inspect all of the other connectors for the circuit. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Illustration 3 g01251634
Terminal locations at the P1 ECM connector for the fan reversing solenoid (P1-12) Fan reversing solenoid (P1-18) Digital return (P1-54) Engine fan reverse switch
Illustration 4 g01155187
Terminal locations at the solenoid connector for the fan reversing solenoid (Terminal 1) Fan reversing solenoid (Terminal 2) Digital 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.
Check the harness and the wiring for abrasion and for pinch points.Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted. The harness and wiring are free of corrosion, of abrasion, and of pinch points.Results:
OK - The connectors and wiring appear to be 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 2. Verify Operation of the Engine Fan Reverse Switch
Connect the Caterpillar Electronic Technician (ET) to the service tool connector.
Turn the battery disconnect switch to the ON position.
Turn the keyswitch to the ON position.
Check the status of the engine fan reverse switch on Cat ET while you operate the switch.
Turn the keyswitch to the OFF position.Expected Result:The status of the switch changes accordingly as you operate the switch.Results:
OK - The status changes accordingly with the switch position. Proceed to Test Step 3.
Not OK - The status does not change with the switch position. Proceed to Test Step 7.Test Step 3. Check for Active Diagnostic Codes
Turn the keyswitch to the ON position.
Use Cat ET to monitor the active diagnostic code screen. Check and record any active diagnostic codes.Note: Wait at least 30 seconds in order for the diagnostic codes to become active.
Determine if the problem is related to an open circuit diagnostic code 05 or a short circuit diagnostic code 06.
Turn the keyswitch to the OFF position.Expected Result:No diagnostic codes are active.Results:
OK - No diagnostic codes are active.Repair: The problem may have been related to a faulty connection in the harness. Carefully reinspect the connectors and wiring. If an intermittent electrical problem is suspected, refer to Troubleshooting, "Electrical Connectors - Inspect" for information that is related to troubleshooting intermittent problems.STOP
Not OK - An open circuit diagnostic code (05) is active at this time. Proceed to Test Step 5.
Not OK - A short circuit diagnostic code (06) is active at this time. Proceed to Test Step 4.Test Step 4. Create an Open Circuit at the Connector for the Fan Reversing Solenoid
Disconnect the harness connectors for the fan reversing solenoid.
Turn the keyswitch to the ON position.
Access the "Active Diagnostic Code" screen on Cat ET. Check for an active open circuit diagnostic code (05) for the fan reversing solenoid.Note: Wait at least 30 seconds in order for the diagnostic codes to become active.
Turn the keyswitch to the OFF position.Expected Result:An open circuit diagnostic code 05 is now active for the fan reversing solenoid.Results:
OK - An open circuit diagnostic code (05) became active after disconnecting the connector.Repair: Temporarily connect a new fan reversing solenoid to the harness, but do not install the new fan reversing solenoid. Verify that there are no active diagnostic codes for the solenoid. If there are no active diagnostic codes for the solenoid, permanently install the new solenoid. Clear any logged diagnostic codes.STOP
Not OK - The short circuit diagnostic code (06) remained active after disconnecting the connector. The short circuit is in the harness between the solenoid connector and the ECM. There may be a problem with the ECM. Leave the solenoid connector disconnected. Proceed to Test Step 6.Test Step 5. Create a Short at the Connector for the Fan Reversing Solenoid
Disconnect the harness connectors at the fan reversing solenoid.
Fabricate a jumper wire that is long enough to create a short c