F439746 Force FUEL PUMP COVER

Table 1
Diagnostic Codes Table
CDL Code J1939 Code Code Description Comments
110-3 110-3 Engine Coolant Temperature Sensor : Voltage Above Normal The code is logged if the engine has been running for more than seven minutes and an open circuit has been detected.
110-4 110-4 Engine Coolant Temperature Sensor : Voltage Below Normal The code is logged. The ECM detects voltage that is not in the acceptable range.
174-3 174-3 Fuel Temperature Sensor : Voltage Above Normal The code is logged. The ECM will flag the fuel temperature as invalid data and the fuel temperature is set to a default value of 40 °C (104 °F).
174-4 174-4 Fuel Temperature Sensor : Voltage Below Normal
1836-3 1385-3 Auxiliary Temperature Sensor : Voltage Above Normal The code is logged. The ECM will flag the temperature as invalid data and the temperature is set to a default value.
1836-4 1385-4 Auxiliary Temperature Sensor : Voltage Below Normal The code is logged. The ECM will flag the temperature as invalid data and the temperature is set to a default value.
2526-3 172-3 Air Inlet Temperature Sensor : Voltage Above Normal The code is logged.
The ECM detects voltage that is not in the acceptable range.
2526-4 172-4 Air Inlet Temperature Sensor : Voltage Below Normal The code is logged.
The ECM detects voltage that is not in the acceptable range.
3372-3 2630-3 Engine Charge Air Cooler #1 Outlet Temperature Sensor : Voltage Above Normal The code is logged.
The ECM detects voltage that is not in the acceptable range.
3372-4 2630-4 Engine Charge Air Cooler #1 Outlet Temperature Sensor : Voltage Below Normal The code is logged.
The ECM detects voltage that is not in the acceptable range.
3386-3 412-3 EGR Temperature Sensor : Voltage Above Normal The code is logged.
This code will not become active during Cold Mode. Run the engine to exit cold mode before troubleshooting a 3386-3 code.
The ECM detects voltage that is not in the acceptable range.
3386-4 412-4 EGR Temperature Sensor : Voltage Below Normal The code is logged.
The ECM detects voltage that is not in the acceptable range.
3683-3 442-3 Auxiliary Temperature #2 : Voltage Above Normal The code is logged.
The ECM detects voltage that is not in the acceptable range.
3683-4 442-4 Auxiliary Temperature #2 : Voltage Below Normal The code is logged.
The ECM detects voltage that is not in the acceptable range. System OverviewThe sensor signal for the passive sensor is routed from the ECM to terminal 1 of each sensor connector. The sensor return for the passive sensors is routed to the ECM from terminal 2 of each sensor connector.Diagnostics on the Caterpillar Electronic Technician (ET)Wiggle Test - The Wiggle Test allows you to monitor the status of the signals from the sensors.For additional information regarding the Wiggle Test, refer to the documentation that accompanies the Cat ET software.
Illustration 1 g03330022
Schematic for the passive analog sensors
Table 2
Troubleshooting Test Steps Values Results
1. Check for Diagnostic Trouble Codes
A. Connect to Cat® Electronic Technician (ET).
B. Turn the keyswitch to the ON position.
C. Access the "Active Diagnostic Code" screen on Cat ET.
Wait at least 30 seconds in order for the diagnostic codes to become active.
D. Look for these active codes or logged codes:
-3
-4
Codes
Result: A -3 diagnostic code is active.
Proceed to Test Step 2.
Result: A -4 diagnostic code is active.
Proceed to Test Step 3.
Result: To troubleshoot a logged 3386-3 or a 412-3 diagnostic code during cold mode, Proceed to Test Step 5.
This code will not become active during cold mode.
Result: For a diagnostic code that is logged but not currently active, Proceed to Test Step 4.
2. Create a Short at the Sensor Connector
A. Turn the keyswitch to the OFF position.
B. Disconnect the suspect sensor.
C. Install the jumper wire between terminal 1 (sensor signal) and terminal 2 (sensor return) at the sensor connector.
D. Turn the keyswitch to the ON position.
E. Monitor the diagnostic codes on Cat ET. Check for an active -4 diagnostic code for the suspect sensor.
Wait at least 30 seconds in order for the diagnostic codes to become active.
F. Turn the keyswitch to the OFF position.
Short Circuit
Result: The -3 diagnostic code remains active for the suspect sensor.
Repair: There is an open in the harness. Repair the wiring or replace the harness.
Verify that the problem is resolved.
Result: A -4 diagnostic code became active after creating the short at the sensor connector.
Repair: The wiring is OK. Replace the sensor.
Verify that the problem is resolved.
3. Create an Open at the Suspect Sensor Connector
A. Turn the keyswitch to the OFF position.
B. Disconnect the sensor connector of the suspect sensor with the active -4 diagnostic code.
C. Turn the keyswitch to the ON position.
D. Monitor the diagnostic codes on Cat ET. Check for an active -3 diagnostic code for the suspect sensor.
Wait at least 30 seconds in order for the diagnostic codes to become active.
A 412-3 or a 3386-3 code will not become active during "Cold Mode". Run the engine to exit cold mode before troubleshooting a 412-3 or a 3386-3 code.
For a 110-3 code, start the engine and let the engine idle for 7 minutes. The engine must be running for at least 7 minutes in order for the diagnostic to run.
E. Turn the keyswitch to the OFF position.
Open Circuit
Result: The -4 diagnostic code remains active for the suspect sensor.
Repair: There is an open in the harness. Repair the wiring or replace the harness.
Verify that the problem is resolved.
Result: A -3 diagnostic code became active after disconnecting the sensor.
Repair: The wiring is OK. Replace the sensor.
Verify that the problem is resolved.
4. Perform the Wiggle Test
Carefully following this procedure is the best way to identify the root cause of an intermittent problem.
A. Turn the keyswitch to the ON position.
B. Use Cat ET to run the "Wiggle Test".
C. Slowly wiggle the wiring and the connectors between the P2 connector and the sensor. Slowly wiggle the wiring and the connectors between the P1 connector and the sensor. Pay particular attention to the wiring near each connector. Be sure to wiggle all of the wiring.
D. As you wiggle the wiring look for these problems.
·