803538 Mariner SWITCH

Table 1
Diagnostic Trouble Codes for the Ignition System for the Aftertreatment Regeneration Device (ARD)    
J1939 Code    Description    Comments    
3473-31     Aftertreatment #1 Failed to Ignite     The ARD has attempted to ignite several times. All of the attempts were unsuccessful. Approximately 10 minutes are required for each attempt.
A "failed to ignite" code may not indicate that there is a problem with the ignition system. There may be a problem with another system such as combustion air or fuel.
Usually, the "failed to ignite" code is accompanied by another logged code that indicates the condition that caused the failure to ignite. The first Test Step in this procedure contains a Table that lists the additional codes.    
Follow the troubleshooting procedure in order to identify the root cause of the problem.    Illustration 1 and Illustration 2 show an overview of the troubleshooting procedure. Follow the steps in order.
Illustration 1 g02721510
Illustration 2 g02721515
Test Step 1. Determine the Type of Cleaning System for the Nozzles Inside the ARD Combustion Head
Illustration 3 g01976876
Typical ARD combustion head (1) Electrical connector for the heated nozzle (ARD combustion head with a heated nozzle) (2) Air line for the pressurized air (ARD combustion head that uses pressurized air for cleaning the nozzles)
Determine the type of cleaning system for the nozzles inside the ARD combustion head. Results:
The ARD purge air system is used to clean the nozzles. - Repair: Contact your local Caterpillar Technical Communicator for information on updating the system. STOP
An electric heating element is used to clean the nozzles. - Proceed to Test Step 2.Test Step 2. Check for Associated Diagnostic Trouble Codes
Establish communication between the Caterpillar Electronic Technician (ET) and the engine ECM.
Table 2 lists the diagnostic trouble codes that are associated with a 3473-31 code. Determine if any of the codes in Table 2 are present.
Table 2
Associated Diagnostic Trouble Codes    
Suspect Parameter Number (SPN)    Failure Mode Identifier (FMI)    Description    
ARD Ignition System    
4265     6     Aftertreatment #1 Transformer Secondary Output : Current Above Normal    
Combustion Air System    
3832     15     Aftertreatment #1 Secondary Air Mass Flow : High - Least Severe (1)    
3832     17     Aftertreatment #1 Secondary Air Mass Flow : Low - Least Severe (1)    
3487     7     Aftertreatment #1 Air Pressure Control : Not Responding Properly    
Fuel System for the ARD    
3480     16     Aftertreatment #1 Fuel Pressure #1 : High - Moderate Severity (2)    
4077     16     Aftertreatment #1 Fuel Pressure #2 : High - Moderate Severity (2)    
4077     17     Aftertreatment #1 Fuel Pressure #2 : Low - Least Severe (1)    
4077     18     Aftertreatment #1 Fuel Pressure #2 : Low - Moderate Severity (2)    
Clean Gas Induction System (CGI)    
520192     15     CGI Mass Flow : High - Least Severe (1)    
520192     16     CGI Mass Flow : High - Moderate Severity (2)    
Nozzle    
3556     7     Aftertreatment Fuel Injector #1 : Not Responding Properly    Results:
An associated diagnostic trouble code is not present. - Proceed to Test Step 3.
An associated diagnostic trouble code is present. - Repair: Troubleshoot the associated diagnostic code.STOPTest Step 3. Perform the ARD Nozzle Heater TestPerform an ARD Nozzle Heater (Current) - Test. Refer to System Operation and Testing and Adjusting, "ARD Nozzle Heater (Current) - Test" for the correct procedure.
Carefully inspect the wire leading to the ARD head. Pull on the wire to verify that the wire is crimped to the terminal and the terminal is properly installed in the connector.
Disconnect the connector where the connector plugs into the engine harness in order to verify that the wiring and terminals are installed correctly. Make the necessary repairs.
Inspect the wiring between the connectors. Look for the following problems and make the necessary repairs:
Damage that is caused by excessive heat
Damage that is caused by chafing
Improper routing of wiring
Damaged insulationExpected Result:The current flow is above 6.0 A for a 12 V system.The current flow is above 3.0 A for a 24 V system.Results:
The current flow agrees with the above results. - The current flow is OK. Proceed to Test Step 4.
The current flow does not agree with the above results. The current flow is low. There may be a problem with the current flow through the heater. - Repair: Determine the cause of the low current flow. Refer to Troubleshooting, "ARD Nozzle Heater - Test".STOPTest Step 4. Check for Spark Voltage at the Spark PlugNote: A 305-2391 Spark Indicator must be used to troubleshoot the ignition system for the Aftertreatment Regeneration Device (ARD). Other types of spark indicators provide incorrect indications.
Illustration 4 g01978667
305-2391 Spark Indicator (3) End of the spark indicator (4) Location on the tool (5) Clip on the adjustable end of the spark indicator (6) "20" indication on the tool
Turn clip (5) until the tip of the threaded rod (4) is set to location (6) .
Disconnect the ignition wire from the spark plug.