16081-ZV1-A00 Honda SCREW, PAN (Honda Code 3749082).

Table 1
Diagnostic Codes for Cooling Fan Control
J1939 Code CDL Code Code Description Comments
- 485-5 Engine Fan Reversing Solenoid : Current Below Normal The current for the fan reversing solenoid control signal is below an acceptable value.
The code is logged.
A warning will appear on the display on the control panel.
The Electronic Control Module (ECM) loses the ability to reverse the engine cooling fan.
- 485-6 Engine Fan Reversing Solenoid : Current Above Normal The current for the fan reversing solenoid control signal is below an acceptable value.
The code is logged.
A warning will appear on the display on the control panel.
The ECM loses the ability to reverse the engine cooling fan. The purpose of a reversing fan is to clean debris from the radiator. This process is done by temporarily reversing the direction of the air flow through the radiator fins 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 engine Electronic Control Module (ECM). The ECM will automatically reverse the direction of the fan rotation. The ECM will use a preset time interval to cycle the fan reversing solenoid.Note: On some applications the fan reversing solenoid may be controlled by a relay. Refer to the appropriate Electrical Schematic.The operator can manually reverse the fan rotation by pressing the engine fan reverse switch. While the momentary switch is depressed, the direction of the fan 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.Use this procedure to troubleshoot any suspect problems with the engine fan reverse switch or the fan reversing solenoid.Refer to the Electrical Schematic for the application while performing the following procedure.
Table 2
Troubleshooting Test Steps Values Results
1. Determine the Diagnostic Code
A. Establish communication between the electronic service tool and the engine Electronic Control Module (ECM). Refer to Troubleshooting, "Electronic Service Tools", if necessary.
B. Download the "Warranty Report" from the engine ECM before performing any troubleshooting or clearing diagnostic trouble codes.
C. Look for one of the diagnostic codes listed in Table 1.
Active Codes
Result: An active or logged 485-5 code is present.
Proceed to Test Step 2.
Result: An active or logged 485-6 code is present.
Proceed to Test Step 3.
Result: An active or logged 486 code is present.
Proceed to Test Step 5.
2. Check for an Open Circuit
A. Turn the keyswitch to the OFF position.
B. Disconnect the engine reversing fan solenoid connector from the wiring harness.
If the solenoid is controlled by a relay, disconnect the relay.
C. Verify that the harness connectors are free of debris, free of corrosion, and was securely connected.
D. If the fan reversing solenoid is controlled by the engine ECM, connect a jumper wire between the terminals of the harness connector for the solenoid. The solenoid coil is replaced with a short circuit.
If the fan reversing solenoid is controlled by a relay, connect a jumper wire between the terminals of the harness connector for the relay solenoid. The solenoid coil is replaced with a short circuit.
E. Turn the keyswitch to the ON position
F. Use the "Engine Reversing Fan Solenoid Override" in the electronic service tool to turn the solenoid ON.
G. Check for active codes.
Short Circuit
Result: A -5 code became active.
An open circuit has been detected in the wiring harness.
Repair: Repair the wiring or replace the wiring.
Proceed to Test Step 4.
Result: A -6 code became active.
The short circuit was detected by the ECM
Repair: Replace the engine reversing fan solenoid relay (if equipped).
If a relay is not equipped, replace the engine reversing fan solenoid.
Proceed to Test Step 4.
3. Check for a Short Circuit
A. Turn the keyswitch to the OFF position.
B. If the fan reversing solenoid is controlled by the engine ECM, disconnect the engine reversing fan solenoid connector from the wiring harness.
If the fan reversing solenoid is controlled by a relay, disconnect the relay.
C. Verify that the harness connector is free of debris, free of corrosion, and was securely connected.
D. Turn the keyswitch to the ON position
E. Check for active codes.
Open Circuit
Result: A -5 code became active.
The open circuit was detected by the ECM.
Repair: Replace the engine reversing fan solenoid relay (if equipped).
If a relay is not equipped, replace the engine reversing fan solenoid.
Proceed to Test Step 4.
Result: A -6 code became active.
A short circuit has been detected.
Repair: Repair the wiring or replace the wiring.
Proceed to Test Step 4.
4. Check the Engine Reversing Fan Operation
A. Start the engine.
B. Activate the engine reversing fan using the engine reversing fan switch.
Switch
Result: The engine reversing fan is not operating properly.
Proceed to Test Step 5.
Result: The engine reversing fan is operating properly.
Return the unit to service.
5. Check the Engine Reversing Fan Switch
A. Disconnect the engine reversing fan solenoid connector from the wiring harness.
B. Use a jumper wire to short circuit the signal and ground wires together on the harness side of the connector for the switch.
C. Turn the keyswitch to the ON position
D. Connect to the electronic service tool. Monitor the engine reversing fan switch parameters in the status screen.
E. Wait at least 30 seconds and check the status of the engine fan reverse switch on the electronic service tool. The correct status for the switch is ONwhile the jumper wire is in place.
F. Remove the jumper wire from the connector. Wait at least 30 seconds and check the status of the engine fan reverse switch on the electronic service tool. The correct status for the switch is OFF with the jumper wire removed.
Status Change
Result: The switch status changed in the electronic service tool.
A failed engine reversing fan switch has been detected.
Repair: Replace the engine reversing fan switch.
Verify that the problem has been resolved. Return the unit to service.
Result: The switch did not change status in the electronic service tool.
A wiring problem between the switch and the ECM has been detected.
Repair: Repair or replace the wiring harness between the switch and the engine harness.
Verify that the problem has been resolved. Return the unit to service.