System Operation Description:
Table 1 lists the diagnostic code that relates to the combustion air system.
Note: Some of the following codes may not be applicable for certain applications.
Note: Refer to Troubleshooting, “Cat ET Service Features” for information about service features.
| Diagnostic Trouble Codes | |||
|---|---|---|---|
| CDL Code | J1939 Code | Description | Comments |
| E1026 (1) | 3474-14 | Aftertreatment #1 Loss of Combustion | The Aftertreatment Regeneration Device (ARD) has stopped generating heat at least four times during an active high speed regeneration. Associated codes may indicate the system that caused the loss of combustion to occur. The code must be cleared with the “Reset All” button on the active diagnostics screen in Caterpillar Electronic Technician (ET). If an active regeneration is initiated with the operator forced regeneration switch, the Engine Control Module (ECM) clears this code automatically. |
| E1026 (2) | 3474-31 | Aftertreatment #1 Loss of Combustion | The ARD has stopped generating heat at least four times during an active regeneration. Associated codes may indicate the system that caused the loss of combustion to occur. The code must be cleared with the “Reset All” button on the active diagnostics screen in Cat ET. If an active regeneration is initiated with the operator forced regeneration switch, the ECM clears this code automatically. |
| Follow the troubleshooting procedure in order to identify the root cause of the problem. | |||
System Operation
The combustion air system routes pressurized air from the outlet of the turbocharger compressor to the ARD. The combustion air is mixed with fuel inside the ARD. The air/fuel mixture is ignited and the air/fuel mixture is burned in order to provide heat for the diesel particulate filter.
Illustration 1 and Illustration 2 show the location of the components for the combustion air system.
Illustration 1 g01943382
Typical combustion air system
(1) Outlet for the combustion air to ARD combustion head
Illustration 2 g02022290
Overview for the ARD combustion head
(2) Flame detection temperature sensor
(3) Electrical connection for the ARD nozzle heater
(4) ARD pilot filter connector
(5) ARD main filter connector
(6) ARD combustion head
(7) ARD spark plug
(8) Inlet for the combustion air
Illustration 3 g02225934
CEM (typical)
(9) Combustion air valve
(10) Inlet for the combustion air valve
(11) Combustion air valve controller
(12) Combustion air absolute pressure sensor
(13) Control group for the combustion air
(14) Piping for the combustion air
(15) ARD combustion head
(16) Inlet for the combustion air to the ARD combustion head
The ECM receives the signal from the combustion air pressure sensor. The ECM uses the signal to determine the amount of combustion air that is flowing to the ARD combustion head.
The ECM creates a pulse width modulated signal that specifies the amount of combustion air that is desired. The ECM sends the signal to the control group.
The actuator for the combustion air receives the PWM signal from the ECM. The actuator for the combustion air moves a spool in the air pressure control valve. The combustion air valve regulates the combustion air to the ARD head.
| Associated Diagnostic Trouble Codes | |
|---|---|
| CDL Code | J1939 Code |
| 2489-7 | 3487-7 |
| 2489-13 | 3487-13 |
| E1050 | 3480-15 or -16 |
| E1052 | 3480-17 or -18 |
| E1051 | 4077-15 or -16 |
| E1053 | 4077-17 or -18 |
| E1045 | 102-18 |
| E1070 | 3556-7 |
| Troubleshooting Test Steps | Values | Results |
|---|---|---|
| 1. Check for Associated Diagnostic Trouble CodesA. Establish communication between Cat ET and the 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. If troubleshooting a 1026 or a 3474 code, access the Aftertreatment Regeneration History in Cat ET. Click on the information tab, then click History, and then click Aftertreatment Regeneration History. If there were three successful regenerations since the code was logged, do not troubleshoot this code. Clear the code and return the unit to service. Table 2 lists the diagnostic trouble codes that are associated with a E1026 code. Determine if any of the codes in Table 2 are present. |
Diagnostic code | Result: An associated diagnostic trouble code is not present.Proceed to Test Step 2.
Result: An associated diagnostic trouble code is present. Refer to Troubleshooting, “Diagnostic Trouble Codes” in order to troubleshoot the associated diagnostic code. |
| 2. Check the Current Flow Through the HeaterA. Verify that the engine is off. Check the current flow through the heater. Refer to Systems Operation/Testing and Adjusting, “ARD Nozzle Heater – Test” for the correct procedure. | Between 7.0 A and 14 A for a 12 V system. Or, between 3.5 A and 7 A for a 24 V system | The current flow is between 7.0 A and 14 A for a 12 V system. Or, the current flow is between 3.5 A and 7 A for a 24 V system.Result: The current flow is OK.
Proceed to Test Step 3. Result: The current flow is not between 7.0 A and 14 A for a 12 V system. Or, the current flow is not between 3.5 A and 7 A for a 24 V system. There may be a problem with the ARD nozzle. Refer to Troubleshooting, “ARD Nozzle – Test”. |
| 3. Perform the “ARD Air System Service Test”A. Reset all active codes and clear all logged codes. Use Cat ET to perform an “ARD Air System Service Test” in order to verify that the problem is resolved. Refer to Troubleshooting, “ARD Combustion Air – Test”. | ARD Air System Service Test | Result: The “ARD Air System Service Test” failed.There is a problem with the ARD combustion air. Refer to Troubleshooting, “ARD Combustion Air – Test”.
Result: The “ARD Air System Service Test” passed. Proceed to Test Step 4. |
Illustration 4 g02360636
(2) Flame detection temperature sensor
| Troubleshooting Test Steps | Values | Results |
|---|---|---|
| 4. Clean the Flame Detection Temperature SensorA. Remove flame detection temperature sensor (2).
B. Clean the flame detection temperature sensor. Use a nonmetallic cleaning pad to clean the sensor. |
Flame detection temperature sensor | Result: The components are clean. The flame detection temperature sensor is not damaged. Install the flame detection sensor.Proceed to Test Step 5.
Result: The flame detection temperature is damaged. Replace flame detection temperature sensor. Proceed to Test Step 5. |
| 5. Check the ARD for Proper OperationA. Reset all active codes and clear all logged codes. Use Cat ET to perform an “ARD Ignition Test” in order to verify that the problem is resolved.
The ARD Ignition Test cannot be performed if the DPF soot loading is above 80%. When the DPF soot loading is above 80%, the Manual DPF Regeneration must be performed using Cat ET. |
ARD ignition test | Result: The test is successful.Proceed to Test Step 8.
Result: The test is not successful. Proceed to Test Step 6. |
Illustration 5 g02623660
ARD head (typical)
(17) Pilot fitting that contains the filter
(18) Main fitting that contains the filter (If equipped)
| Troubleshooting Test Steps | Values | Results |
| 6. Replace the Fittings that Contain the Filter in the ARD HeadA. Replace the fittings that contain the filters in the ARD head.
B. Reset all active codes and clear all logged codes by cycling the keyswitch to the Off position. C. Perform the “ARD Ignition Test” using Cat ET. Refer to System Operation and Testing and Adjusting , “ARD Fuel System – Test”. The ARD Ignition Test cannot be performed if the DPF soot loading is above 80%. When the DPF soot loading is above 80%, the Manual DPF Regeneration must be performed using Cat ET. |
Filter fittings | Result: The “ARD Ignition Test” was successful and no codes were logged.Proceed to Test Step 8.
Result: The “ARD Ignition Test” was not successful. Proceed to Test Step 7. |
Illustration 6 g02623311
(19) Fouled slot
Illustration 7 g02623312
(20) Acceptable soot accumulation
| Troubleshooting Test Steps | Values | Results |
|---|---|---|
|
7. Inspect ARD Swirl Plate
A. Remove ARD head. Refer to Disassembly and Assembly, “Combustion Head Group (ARD) – Remove and Install – Clean Emissions Module” for the proper procedure to remove the ARD combustion head. Soot accumulation is normal. Slot fouling is defined as more than 1/2 the inner row slots being completely blocked. Partially blocked inner row slots are normal and do not affect regeneration performance. Refer to Illustrations 6 and 7 to verify if the swirl plate is fouled. B. Inspect the swirl plate for fouled slots. Refer to Illustrations 6 and 7 to verify if the swirl plate is fouled. |
Swirl plate |
Result: The swirl plate is fouled.
Clean the swirl plate. Refer to Testing and Adjusting, “Swirl Plate (ARD Combustion) – Inspect/Clean “. Reset all active codes and clear all logged codes. Perform the “ARD Ignition Test” in Cat ET and verify that there are no fuel leaks. The ARD Ignition Test cannot be performed if the DPF soot loading is above 80%. When the DPF soot loading is above 80%, the Manual DPF Regeneration must be performed using Cat ET. Proceed to Test Step 8. Result: The swirl plate is not fouled. Replace the ARD combustion head. Refer to Special Instruction, REHS4824, “Replacement of the ARD Combustion Head on Caterpillar Products with Clean Emissions Modules”. Reset all active codes and clear all logged codes. Perform the “ARD Ignition Test” in Cat ET and verify that there are no fuel leaks. The ARD Ignition Test cannot be performed if the DPF soot loading is above 80%. When the DPF soot loading is above 80%, the Manual DPF Regeneration must be performed using Cat ET. Proceed to Test Step 8. |
|
8. Perform a “Manual DPF Regeneration”
This test must be performed through Cat ET. The Cat ET service tool enhances the diagnostics during the service test. A. Clear all diagnostic codes. B. Click the “Disconnect” icon on Cat ET in order to disconnect Cat ET from the engine ECM. C. Turn the keyswitch to the Off position. Wait for five seconds. D. Turn the keyswitch to the On position. E. Click the “Connect” icon on Cat ET in order to connect Cat ET to the engine ECM. F. Start the engine. Allow the engine to idle for three minutes. Do not use the operators switch for a stationary regeneration. The service tests provide enhanced diagnostics that are necessary for proper troubleshooting and repair. G. Start a “Manual DPF Regeneration” in Cat ET. The ECM tests the nozzles for plugging after the “Manual DPF Regeneration” is complete. Approximately 10 minutes are required in order for the test to provide a result. A code will become active if the nozzles are plugged. |
Manual DPF Regeneration |
Result: The “Manual DPF Regeneration” completed successfully. There are no additional codes.
Return the unit to service. Result: The “Manual DPF Regeneration” did not complete successfully. There are additional codes. Troubleshoot the additional codes before returning the unit to service. Refer to Troubleshooting for the correct procedure. Verify that the problem is resolved. |
Test Step 1.
Complete the procedure in the order in which the steps are listed.
Results:
- The procedure corrected the issue. – STOP
- The procedure did not correct the issue. –Repair: Contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).
STOP