C3.4B Engines DEF Pump - Test Caterpillar

DEF Pump - Test

C3.4B Engines [UENR4499]

C3.4B Engines DEF Line Heater - Test

C3.4B Engines DEF Return Valve - Test

AIR INLET AND EXHAUST SYSTEM

AFTERTREATMENT GP

C3.4B Engines DEF Concentration Is Incorrect

C3.4B Engines DEF Module Does Not Respond

C3.4B Engines DEF Pressure Is High

C3.4B Engines DEF Does Not Purge

C3.4B Engines DEF Pressure Does Not Respond

C3.4B Engines DEF Pressure Is Low

C3.4B Engines DEF Tank Level Is Low

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Table 1
Diagnostic Trouble Codes for the DEF Pump
J1939 Code	Code Description	Comments
4374-7	Aftertreatment #1 Diesel Exhaust Fluid Pump Motor Speed : Not Responding Properly	The Electronic Control Module (ECM) detects that the Diesel Exhaust Fluid (DEF) pump speed is not responding as expected to the speed command from the ECM. The ECM has restarted the pump 5 times since the last keyswitch cycle. The warning lamp will come on.
4374-10	Aftertreatment #1 Diesel Exhaust Fluid Pump Motor Speed : Abnormal Rate of Change	The ECM Detects that the DEF pump motor speed has deviated from the required speed between 4.5 and 5.5 seconds. The warning lamp will come on.
4374-15	Aftertreatment #1 Diesel Exhaust Fluid Pump Motor Speed : High - least severe (1)	The ECM detects that the duty cycle of the DEF pump required to maintain DEF pressure is too high. The DEF system is not dosing. The battery voltage is at least 10 V. The warning lamp will flash. The engine will be derated.
4374-16	Aftertreatment #1 Diesel Exhaust Fluid Pump Motor Speed : High - moderate severity (2)	The ECM detects that the PWM duty cycle for the DEF pump speed is greater than 86 percent. The battery voltage is at least 10 V. The warning lamp will come on.
4374-18	Aftertreatment #1 Diesel Exhaust Fluid Pump Motor Speed : Low - moderate severity (2)	The ECM detects that the PWM duty cycle for the DEF pump speed is less than 4 percent. The battery voltage is at least 10 V. The warning lamp will come on.
4375-16	Aftertreatment #1 DEF Pump Drive Command : High - moderate severity (2)	The ECM detects that the PWM duty cycle for the DEF pump control is greater than 86 percent. The battery voltage is at least 10 V. The warning lamp will come on.
4375-18	Aftertreatment #1 DEF Pump Drive Command : Low - moderate severity (2)	The ECM detects that the PWM duty cycle for the DEF pump control is less than 4 percent. The battery voltage is at least 10 V. The warning lamp will come on.
5435-5	Aftertreatment #1 DEF Pump State : Current Below Normal	The ECM detects low current condition on the DEF pump motor circuit for at least 0.5 seconds. The battery voltage is at least 10 V. The warning lamp will come on.
5435-6	Aftertreatment #1 DEF Pump State : Current Above Normal	The ECM detects a high current condition on the DEF pump motor circuit for at least 0.2 seconds. The SCR relay is closed. The warning lamp will come on.
5435-7	Aftertreatment #1 DEF Pump State : Not Responding Properly	The ECM is unable to communicate with the DEF pump module for three consecutive attempts. The warning lamp will come on.
5706-16	Aftertreatment #1 Diesel Exhaust Fluid Pump Heater : High - moderate severity (2)	The ECM detects that the PWM duty cycle for the DEF pump temperature is greater than 86 percent. The battery voltage is at least 10 V. The warning lamp will come on.
5706-18	Aftertreatment #1 Diesel Exhaust Fluid Pump Heater : Low - moderate severity (2)	The ECM detects that the PWM duty cycle for the DEF pump temperature is less than 4 percent. The battery voltage is at least 10 V. The warning lamp will come on.
5707-15	Aftertreatment #1 Diesel Exhaust Fluid Pump Heater Command : High - least severe (1)	The ECM detects that the PWM duty cycle for the DEF pump temperature command signal is greater than 86 percent. The battery voltage is at least 10 V. The warning lamp will come on.
5707-17	Aftertreatment #1 Diesel Exhaust Fluid Pump Heater Command : Low - least severe (1)	The ECM detects that the PWM duty cycle for the DEF pump temperature command signal is less than 4 percent. The battery voltage is at least 10 V. The warning lamp will come on.
Follow the troubleshooting procedure in order to identify the root cause of the problem.

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Illustration 1	g03872331
Schematic diagram for the DEF pump Not all connectors are shown. Refer to the Electrical Schematic for the application.

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Illustration 2	g03720378
View of the pin locations on the P1 connector for the DEF pump (72) DEF pump motor control signal (76) DEF pump motor signal feedback

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Illustration 3	g03720379
Pin locations on the DEF pump module connector (2) DEF pump motor control signal/feedback (3) DEF pump motor (+) (4) DEF pump motor (-)

DEF Dosing System Verification Test

This test primes the dosing system. The test is used to ensure that the DEF pump is able to build adequate pressure.

This test turns on the DEF pump. During this time, the DEF pump will pressurize the entire DEF dosing system. The DEF injector will open briefly. The DEF pump will purge the system at the end of the test.

Navigate to the following menu options in order to access the "DEF Dosing System Verification Test":

Diagnostics
Diagnostic Tests

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Table 2
Troubleshooting Test Steps	Values	Results
1. Inspect Electrical Connectors and Wiring A. Check the fuses. B. Inspect the P1/J1 ECM connectors. C. Inspect the connector for the DEF pump module. D. Inspect the connectors for the SCR Relay. E. Perform a 30 N (6.7 lb) pull test on each of the wires in the ECM connector and the connector for the DEF pump. F. Check all of the wiring associated with the DEF pump for abrasions and pinch points.	Damaged wire or connector	Result: A damaged wire or damaged connector was not found. The fuses are OK Proceed to Test Step 2. Result: A damaged wire or damaged connector was found. A fuse is blown. Repair: Repair the damaged wire or the damaged connector. Replace any blown fuses. Use the electronic service tool to clear all logged diagnostic codes. Verify that the repair eliminates the fault.
2. Check for Active or Recently Logged Diagnostic Codes A. Connect the electronic service tool to the diagnostic connector. Refer to Troubleshooting, "Electronic Service Tools" B. Look for active or logged diagnostic codes.	Diagnostic Trouble Codes	Result: A 4374-7 or 4374-10 diagnostic code is active or recently logged. Proceed to Test Step 3. Result: One of the following diagnostic codes is active or recently logged: · 4374-16 · 4374-18 · 4375-16 · 4375-18 · 5435-5 · 5435-6 · 5706-16 · 5706-18 · 5707-15 · 5707-17 Proceed to Test Step 4. Result: A 5435-7 diagnostic code is active or recently logged. Proceed to Test Step 7.
3. Check for Frozen DEF A. If the ambient temperature is below 0° C (32° F), check that the DEF heaters are working correctly. Refer to Troubleshooting, "DEF Line Heater - Test".	Frozen DEF	Result: The DEF heaters were not working correctly. Repair: Make any necessary repairs. Refer to Troubleshooting, "DEF Line Heater - Test". Result: The DEF lines are not frozen. The DEF heaters are working correctly. Repair: Replace the DEF pump module. Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault.
4. Check the Power Supply to the DEF Pump Motor A. Turn the keyswitch to the OFF position. B. Disconnect the harness connector for the DEF pump module. C. Turn the keyswitch to the ON position. D. Use a multimeter to measure the voltage between terminal 3 on the harness connector for the DEF pump module and a suitable ground. E. Turn the keyswitch to the OFF position.	10 V to 14 V	Result: The measured voltage is not within the expected range. Repair: Check the fuse. If the fuse is blown, there may be a short in the wiring between the DEF pump module and the SCR relay. Replace the faulty wiring. Proceed to Test Step 9. If the fuse is not blown, proceed to Test Step 5. Result: The measured voltage is within the expected range. Proceed to Test Step 6.
5. Check the Wiring Between the DEF Pump Module and the SCR Relay A. Turn the keyswitch to the OFF position. B. Disconnect the SCR relay. C. Use a multimeter to measure the resistance between terminal 3 on the harness connector for the DEF pump module and terminal 87 on the harness connector for the SCR relay.	Less than 5 Ohms	Result: The measured resistance is greater than 5 Ohms. The fault is in the wiring between the DEF pump module and the SCR relay. Repair: Replace the faulty wiring. Proceed to Test Step 9. Result: The measured resistance is less than 5 Ohms. Repair: There may be a fault in the circuit for the SCR relay. Refer to Troubleshooting, "Relay - Test (SCR Relay)" in order to Troubleshoot this circuit.
6. Check the Ground Wiring for the DEF Pump Motor A. Turn the keyswitch to the OFF position. B. Use a multimeter to measure the resistance between terminal 4 on the harness connector for the DEF pump module and a suitable ground.	Less than 5 Ohms	Result: The measured resistance is greater than 5 Ohms. There is a fault in the ground connection for the DEF pump motor. Repair: Check the ground connections. If necessary, replace the ground wiring for the DEF pump module. Result: The measured resistance is less than 5 Ohms. Proceed to Test Step 7.
7. Check the DEF Pump Motor Signal/Feedback Wiring for an Open Circuit A. Turn the keyswitch to the OFF position. B. Disconnect the DEF pump module connector. Disconnect the P1 connector from the ECM. C. Use a multimeter to measure the resistance between the following points: · Terminal 2 on the DEF pump module harness connector and P1:72 · Terminal 2 on the DEF pump module harness connector and P1:76	Less than 5 Ohms	Result: At least one of the resistance measurements is greater than 5 Ohms. The fault is in the wiring between the DEF pump module connector and the P1 ECM connector. Repair: Replace the faulty wiring. Proceed to Test Step 9. Result: Both resistance measurements are less than 5 Ohms. Proceed to Test Step 8.
8. Check the DEF Pump Motor Signal/Feedback Wiring for a Short Circuit A. Turn the keyswitch to the OFF position. B. Disconnect the P1 connector from the ECM. C. Use a multimeter to measure the resistance between P1:72 and all other terminals on the P1 connector except P1:76. D. Use a multimeter to measure the resistance between P1:76 and all other terminals on the P1 connector except P1:72.	Greater than 1 k Ohm	Result: At least one of the resistance measurements is less than 1 k Ohm. There is a short in the DEF pump signal feedback wiring. Repair: Replace the faulty wiring. Proceed to Test Step 9. Result: All resistance measurements are greater than 1 k Ohm. Proceed to Test Step 9.
9. Run the "DEF Dosing System Verification Test" A. Turn the keyswitch to the OFF position. B. Reconnect all electrical connectors and reinstall any DEF lines that may have been removed. C. Connect the electronic service tool to the diagnostic connector. D. Start the engine. E. Use the electronic service tool to run the "DEF Dosing System Verification Test". F. Check that the "DEF Dosing System Verification Test" completed successfully and that none of the diagnostic codes listed in Table 1 are active.	Test Successful	Result: The "DEF Dosing System Verification Test" completed successfully. There are no active diagnostic codes. Return the engine to service. Result: A diagnostic code other than those listed in Table 1 is active. Repair: Troubleshoot any other diagnostic codes. Refer to Troubleshooting, "Diagnostic Trouble Codes". Result: The "DEF Dosing System Verification Test" was not successful. One of the diagnostic codes listed in Table 1 is still active. Contact the Dealer Solution Network (DSN).