C7.1 Engines and Generator Sets Caterpillar

Use this procedure to troubleshoot excessive soot in the Diesel Particulate Filter (DPF). Also use this procedure if one of the following event codes are active. Refer to Troubleshooting, "Event Codes" for information about event codes. For information on the engine monitoring system, refer to Troubleshooting, "Engine Monitoring System".

Note: Certain systems will display multiple codes for troubleshooting. These associated codes must be used to troubleshoot the system effectively. Refer to Troubleshooting, "General Information" for additional information.

Note: Refer to Troubleshooting, "Service Tool Features" for information about service features.

The Engine Control Module (ECM) maintains an estimate of the soot load in the Diesel Particulate Filter (DPF). The estimate is based on the engine operating conditions. If the ECM estimates that the soot load is excessive, the ECM activates the applicable code.

Note: When the regeneration completes, the active soot loading code will not change to a logged code or clear for 5 minutes.

Table 1

Diagnostic Trouble Codes
J1939 Codes	CDL Code	Code Description (code descriptions may vary)	Comments
3714-31	E992 (3)	DPF Active Regeneration Inhibited Due to Temporary System Lockout	The engine has been running for 10 minutes after the code was activated. The electronic service tool "Manual Diesel Particulate Filter Regeneration" must be initiated.
3715-31	E991 (3)	DPF Active Regeneration Inhibited Due to Permanent System Lockout	The estimated soot load is high. The engine may not operate correctly. Factory passwords are required to clear this code.
3719-0	E995 (3)	High DPF #1 Soot Loading	The estimated soot load is high. Engine operation is limited to 60 second intervals when the electronic service tool is not communicating with the ECM.
3719-16	E995 (2)	High DPF #1 Soot Loading	The estimated soot load is high. The ECM shuts down the engine when this code becomes active for the first time. The engine can be started and operated. Engine power is gradually derated as the soot load increases.
Follow the troubleshooting procedure to determine the root cause of the problem.

Note: Engine operation must be kept to a minimum to minimize the amount of soot that is created. Follow the troubleshooting procedure to minimize the amount of engine operation.

Complete the procedure in the order in which the steps are listed.

Table 2

Troubleshooting Test Steps	Values	Results
1. Active Codes and Logged Codes A. Establish communication between the electronic service tool and the Electronic Control Module (ECM). B. Look for the following codes: 1. 3719-16 (E995 (2)) 2. 3719-0 (E995 (3)) 3. 3715-31 E991 (3) 4. 3714-31 E992 (3)	Codes	Result: A 3715-31 (E991 (3)) code is present. Proceed to Test Step 2. Result: One of the following codes are present: 1. 3719-16 (E995 (2)) 2. 3719-0 (E995 (3)) 3. 3714-31 (E992 (3)) Proceed to Test Step 3.
2. 3715-31 (E991 (3)) Code A. The 3715-31 (E991 (3)) code indicates that the engine has continued to run after repeated warnings and engine shutdowns. The DPF must be replaced.	DPF	Result: A 3715-31 (E991 (3)) or code is present. Repair: Replace the DPF. Refer to the Disassembly and Assembly, "Diesel Particulate Filter - Remove and Install (Clean Emissions Module)" for the correct procedure. After the DPF has been replaced, clear the 3715-31 (E991 (3)) code (a factory password will be necessary) and proceed to Test Step 3

Table 3

Associated Diagnostic Trouble Codes
J1939 Code	CDL Code
102-18	E1045 (2)
3474-31	E1026 (2)
3473-31	E1025 (2)
3703-31	E993 (2)
3609-15	E1156 (1)
3711-31	E593 (2)
3750-31	E1239 (1)
3474-14	E1026 (1)
3716-31	E1300 (2)

Table 4

Troubleshooting Test Steps	Values	Results
3. Associated Codes A. Establish communication between the electronic service tool and the Electronic Control Module (ECM). B. Check the electronic service tool for any associated codes that are listed in Table 3.	Associated Codes	Result: An associated code is active or logged. Troubleshoot any codes that are present before continuing with this procedure. Result: An associated code is not active or logged. Proceed to Test Step 4.
4. Current Flow through the ARD Nozzle Heating Element A. Start the engine. B. Use a clamp-on ammeter to check the current flow through the ARD nozzle heating element.	Between 7 A and 14 A for a 12 V system Between 3.5 A and 7 A for a 24 V system	Result: The current flow is acceptable. Proceed to Test Step 5. Result: The current flow is not acceptable. Repair: Refer to Troubleshooting, "ARD Nozzle - Test" for the correct procedure.
5. ARD Combustion Air Test A. Perform the "ARD Air System Service" test.	Combustion Air Test	Result: The test results are unacceptable. Repair: Perform the following procedure: 1. Perform the Cylinder Cutout Test on the electronic service tool. If there is a fault with injection, make the necessary repairs and proceed to Test Step 6. If there is not a fault with injection, continue with this procedure. 2. Remove the inlet section from the DPF. Inspect inside inlet section and the front face of the DPF. Look for oil and for excessive soot. The presence of a small amount of soot is a normal condition. If the amount of soot is considered to be excessive, contact the Dealer Solutions Network (DSN). Continue with this procedure after guidance has been received from the DSN. If oil is found, inspect the outlet of the turbocharger. If oil is found, contact the Dealer Solutions Network (DSN). Continue with this procedure after guidance has been received from the DSN. Clean the oil from inside the inlet section of the DPF and the front face of the DPF. Assemble the DPF. Run the engine at 1400 rpm for 15 minutes. Then, proceed to Test Step 6. Result: The test results are acceptable. Proceed to Test Step 6.
6. Manual DPF Regeneration Do not use the cab switch for a stationary DPF regeneration. The service tests provide enhanced diagnostics that are necessary for proper troubleshooting and repair. A. Start a "Manual DPF Regeneration" in the electronic service tool.	Manual DPF Regeneration	Result: The "Manual DPF Regeneration" was successful. Return the engine to service. Result: The "Manual DPF Regeneration" not was successful. Repair: Troubleshoot the diagnostic codes that are present or contact the Dealer Solutions Network (DSN).