PLATE 4W2171 - Caterpillar

Table 1
CDL Code Description
(code descriptions may vary) System Response
485-5 Engine Fan Reverse Actuator : Current Below Normal Engine Fan Reversing Solenoid: Current Below NormalThis code indicates that there is an open circuit in the engine reversing fan solenoid circuit.
485-6 Engine Fan Reversing Solenoid: Current Above Normal This code indicates that there is a short circuit in the engine reversing fan solenoid circuit.
Illustration 1 g03685569Complete the procedure in the order in which the steps are listed.
Table 2
Troubleshooting Test Steps Values Results
1. Determine the Diagnostic Code
A. Establish communication between Cat® Electronic Technician (ET) 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 an active or logged -5 code or -6 code.
Active Codes
Result: An active or logged -5 code is present.
Proceed to Test Step 2.
Result: An active or logged -6 code is present.
Proceed to Test Step 3.
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.
C. Verify that the harness connector is free of debris, free of corrosion, and was securely connected.
D. Connect a jumper wire between the terminals of the harness connector for the engine reversing fan 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 Cat ET 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.
Proceed to Test Step 4.
3. Check for a Short Circuit
A. Turn the keyswitch to the OFF position.
B. Disconnect the engine reversing fan solenoid connector from the wiring harness.
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.
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 Cat ET. Monitor the engine reversing fan switch parameters in the status screen.
E. Wait