3516E Engine for Tier 4 Final 994K Wheel Loaders Caterpillar

DEF Does Not Purge

Usage:

994K SMX

Use this procedure to troubleshoot a Diesel Exhaust Fluid (DEF) system purge failure. Also, use this procedure if one of the following event codes is active or logged.

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Table 1
J1939 Code and Description	CDL Code and Description	Comments
3362-14 Aftertreatment #1 DEF Dosing Unit Input Lines : Special Instruction	E114 (2) Aftertreatment #1 DEF Dosing Unit #1 Input Lines Not Purged (2)	Aftertreatment #1 DEF pump #1 did not completely purge the DEF system after the engine was turned off. The code is logged.
4452-14 Aftertreatment #2 DEF Dosing Unit #1 Input Lines : Special Instruction	E1664 (2) Aftertreatment #2 DEF Dosing Unit #1 Input Lines Not Purged (2)	Aftertreatment #2 DEF pump #1 did not completely purge the DEF system after the engine was turned off. The code is logged.
7458-14 Aftertreatment #1 DEF Dosing Unit #2 Input Lines : Special Instruction	E1663 (2) Aftertreatment #1 DEF Dosing Unit #2 Input Lines Not Purged (2)	Aftertreatment #1 DEF pump #2 did not completely purge the DEF system after the engine was turned off. The code is logged.
7463-14 Aftertreatment #2 DEF Dosing Unit #2 Input Lines : Special Instruction	E1665 (2) Aftertreatment #2 DEF Dosing Unit #2 Input Lines Not Purged (2)	Aftertreatment #2 DEF pump #2 did not completely purge the DEF system after the engine was turned off. The code is logged.

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Table 2
Associated Codes
J1939 Code	CDL Code	Troubleshooting Procedure
3361-5	3102-5	Troubleshooting, DEF Pump Motor - Test
3361-6	3102-6	Troubleshooting, DEF Pump Motor - Test
4334-15	3090-20	Troubleshooting, DEF Pressure Is High
4334-16	E930 (1)	Troubleshooting, DEF Pressure Is High
4376-5	3862-5	Troubleshooting, DEF Return Valve - Test
4376-6	3862-6	Troubleshooting, DEF Return Valve - Test
4376-14	3862-14	Troubleshooting, DEF Return Valve - Test
4387-15	3091-20	Troubleshooting, DEF Pressure Is High
4387-16	E932 (1)	Troubleshooting, DEF Pressure Is High
4442-5	5009-5	Troubleshooting, DEF Return Valve - Test
4442-6	5009-6	Troubleshooting, DEF Return Valve - Test
4442-14	5009-14	Troubleshooting, DEF Return Valve - Test
4451-5	3109-5	Troubleshooting, DEF Pump Motor - Test
4451-6	3109-6	Troubleshooting, DEF Pump Motor - Test
5966-6	3965-6	Troubleshooting, DEF Control Module Power - Test
5968-6	4801-6	Troubleshooting, DEF Control Module Power - Test
6309-6	3966-6	Troubleshooting, DEF Control Module Power - Test
6310-6	4802-6	Troubleshooting, DEF Control Module Power - Test
7457-5	5032-5	Troubleshooting, DEF Pump Motor - Test
7457-6	5032-6	Troubleshooting, DEF Pump Motor - Test
7459-15	5006-20	Troubleshooting, DEF Pressure Is High
7459-16	E1705 (1)	Troubleshooting, DEF Pressure Is High
7462-5	5033-5	Troubleshooting, DEF Pump Motor - Test
7462-6	5033-6	Troubleshooting, DEF Pump Motor - Test
7464-15	5007-20	Troubleshooting, DEF Pressure Is High
7464-16	E1707 (1)	Troubleshooting, DEF Pressure Is High
7522-6	4799-6	Troubleshooting, DEF Control Module Power - Test
7523-6	4800-6	Troubleshooting, DEF Control Module Power - Test
7533-6	4803-6	Troubleshooting, DEF Control Module Power - Test
7534-6	4804-6	Troubleshooting, DEF Control Module Power - Test
7536-5	5008-5	Troubleshooting, DEF Return Valve - Test
7536-6	5008-6	Troubleshooting, DEF Return Valve - Test
7536-14	5008-14	Troubleshooting, DEF Return Valve - Test
7537-5	5010-5	Troubleshooting, DEF Return Valve - Test
7537-6	5010-6	Troubleshooting, DEF Return Valve - Test
7537-14	5010-14	Troubleshooting, DEF Return Valve - Test

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NOTICE

Wait 2 minutes after the engine has stopped before turning the battery disconnect switch to the OFF position. The Diesel Exhaust Fluid (DEF) system requires 2 minutes to purge DEF from system components automatically. Failing to complete the purge could damage the Selective Catalyst Reduction (SCR) system.

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Table 3
Required Tools
Part Number	Part Name	Qty
372-5260	Test Lead Tool Group	1

Probable Causes

Codes
Lamp
Voltage
Signal
System state
Wiring harness

Recommended Actions

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Table 4
Troubleshooting Test Steps	Values	Results
1. Check for Codes A. Connect Cat ET. B. Look for active codes that are associated with the system for the event code.	Codes	Result: An associated code is active. Repair: Troubleshoot the associated code before continuing with this test. Result: All the following codes are active: - 3362 or E114 - 4452 or E1664 - 7458 or E1663 - 7463 or E1665 Proceed to Test Step 2. Result: One of the following codes is active: - 3362 or E114 - 4452 or E1664 - 7458 or E1663 - 7463 or E1665 Proceed to Test Step 6.
2. Operate the Engine A. Start the engine. B. Run the engine until normal operating temperature is reached. C. Connect Cat ET. D. Use Cat ET to monitor the following: - Aftertreatment SCR System State Note: The Aftertreatment SCR System State is on the Aftertreatment status screen on the Selective Catalyst Reduction System ECM. E. Check for codes when the "Aftertreatment SCR System State" reads "Normal Dosing Operation".	Codes	Result: A code is not active. Proceed to Test Step 3. Result: A code remains active while running the engine and another code becomes active. Repair: Troubleshoot the code that came active while running the engine. Verify that the repair eliminated the problem.
3. Check the Operation of the "Wait to Disconnect Lamp" A. Start the engine. B. Run the engine until normal operating temperature is reached. C. Connect Cat ET. D. Use Cat ET to monitor the following: - Aftertreatment SCR System State Note: The Aftertreatment SCR System State is on the Aftertreatment status screen on the Selective Catalyst Reduction System ECM. E. Check the operation of the "Wait to Disconnect Lamp" when the "Aftertreatment SCR System State" reads "Normal Dosing Operation".	Lamp	Result: The "Wait to Disconnect Lamp" is illuminated while the "Aftertreatment SCR System State" reads "Normal Dosing Operation". Return to service. Result: The "Wait to Disconnect Lamp" is not illuminated while the "Aftertreatment SCR System State" reads "Normal Dosing Operation". Repair: Replace the "Wait to Disconnect Lamp" bulb. If the problem is not resolved, proceed to Test Step 4.
4. Check for Power at the "Wait to Disconnect Lamp" A. Check for 24 VDC at terminal 1 of the "Wait to Disconnect Lamp".	24 VDC	Result: There was 24 VDC at terminal 1 of the "Wait to Disconnect Lamp". Proceed to Test Step 5. Result: There was not 24 VDC at terminal 1 of the "Wait to Disconnect Lamp". Repair: Repair the wiring harness. If the problem is not resolved, proceed to Test Step 5.
5. Check for Ground Signal at the "Wait to Disconnect Lamp" A. Start the engine. B. Run the engine until normal operating temperature is reached. C. Connect Cat ET. D. Use Cat ET to monitor the following: - Aftertreatment SCR System State Note: The Aftertreatment SCR System State is on the Aftertreatment status screen on the Selective Catalyst Reduction System ECM. E. Check the operation of the "Wait to Disconnect Lamp" when the "Aftertreatment SCR System State" reads "Normal Dosing Operation".	Ohms	Result: There were more than 10K Ohms between terminal 2 of the "Wait to Disconnect Lamp" and a known good ground. Repair: There is an open circuit between the engine ECM and the "Wait to Disconnect Lamp" socket. Repair the wiring harness. Result: There were less than 10K Ohms between terminal 2 of the "Wait to Disconnect Lamp" and a known good ground. If the problem is not resolved, proceed to Test Step 6.
6. Verify that the "Aftertreatment System State" Changed to "Purging" at Engine Shutdown for the Aftertreatment System that has the Active Failure to Purge Event Code A. Start the engine. B. Run the engine until normal operating temperature is reached. C. Connect Cat ET. D. Use Cat ET to monitor the following: - Aftertreatment SCR System State Note: The Aftertreatment SCR System State is on the Aftertreatment status screen on the Selective Catalyst Reduction System ECM. E. Check the operation of the "Wait to Disconnect Lamp" when the "Aftertreatment SCR System State" reads "Normal Dosing Operation". F. Turn the keyswitch to the OFF position to stop the engine. G. Turn the keyswitch to the ON position. H. Connect Cat ET. J. Use Cat ET to monitor the following: - Aftertreatment SCR System State Note: The Aftertreatment SCR System State is on the Aftertreatment status screen on the Selective Catalyst Reduction System ECM.	System State	Result: A code is not active and all four "Aftertreatment SCR System States" changed to "DEF Purging" when the engine is stopped. Proceed to Test Step 3. Result: One of the four "Aftertreatment SCR System States" did not change to "DEF Purging" after the engine speed reached zero RPM. Proceed to Test Step 7.
7. Check the Diesel Exhaust Fluid Controller (DCU) Key Switch Sink Output Wire for an Open A. Turn the keyswitch to the OFF position. B. Disconnect the J1 and J2 connector from the aftertreatment ECM. C. Disconnect the 53-pin connector from the affected DCU. D. Connect the 398-5063 Probe to the DCU connector. The probe must be used to prevent damage to the DCU connector. E. Measure the resistance between the following pins on the affected DCU wiring harness connector: - For DCU #1 measure between pin 29 on the 70-pin SCR Controller J1 connector and pin 52 on the DCU. - For DCU #2 measure between pin 30 on the 70-pin SCR Controller J1 connector and pin 52 on the DCU. - For DCU #3 measure between pin 31 on the 70-pin SCR Controller J1 connector and pin 52 on the DCU. - For DCU #4 measure between pin 36 on the 70-pin SCR Controller J1 connector and pin 52 on the DCU.	Ohms	Result: There were greater than 10K ohms between pin 52 and the respective wire on the J1 ECM connector. Repair: A failed wiring harness has been detected. Replace the wiring harness. Proceed to Test Step 8. Result: There were less than 10K ohms between pin 52 and the respective wire on the J1 ECM connector. Proceed to Test Step 8.
8. Perform an "Aftertreatment Dosing System Functional Test" A. Connect Cat ET. B. Select the "Selective Catalyst Reduction System". C. Use Cat ET to perform the following diagnostic test: - "Aftertreatment Dosing System Functional Test"	Test	Result: The test was successful. Return to service.

If the procedure did not correct the issue, contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).