PLATE 9T8455 - Caterpillar

System Operation Description:This procedure covers the following diagnostic code:
Table 1
Diagnostic Trouble Codes for the ARD Nozzle    
J1939 Code     Description     Notes    
3556-7     Aftertreatment Fuel Injector #1 : Not Responding Properly     The fuel flow to the Aftertreatment Regeneration Device (ARD) fuel nozzle is restricted.    The ARD nozzle can become plugged with carbon or with debris. The Electronic Control Module (ECM) periodically tests the condition of the nozzle. The engine is equipped with a system that cleans the nozzle. A restriction in a filter connector for the ARD combustion head can also set this code.Electric Heating Element - The ARD combustion head contains an electric heating element. The heating element operates periodically in order to clean the nozzle.Features on the Electronic Service ToolARD Nozzle Heater Test - This process activates the output for the heated nozzle in order to test the nozzle heater circuit. The output only remains activated when selected on the electronic service tool. The heat cycle stops if the engine is stopped.ARD Fuel Nozzle Heater Override - This process activates the output for the heated nozzle in order to clean the nozzle. The output remains activated for approximately 1 hour. The heat cycle stops if the engine is stopped. The heat cycle continues when the engine is started. Active regenerations will not occur until the heat cycle is complete.ARD Ignition Test - The test operates the ARD for approximately 5 minutes while the engine is running. The test determines if the ARD can generate heat. If the ARD cannot generate heat, a diagnostic code is activated. The code indicates the specific problem with the ARD.Test Step 1. Check for Active or Recently Logged Diagnostic Codes
Turn the keyswitch to the ON position.
Establish communication between the electronic service tool and the ECM . Refer to Troubleshooting, "Electronic Service Tools", if necessary.
Download the following items before performing any troubleshooting or clearing any diagnostic codes:
Warranty Report
Aftertreatment Regeneration Trigger History
Product Status Report with Histograms
The ignition system may cause an electrical shock hazard, which may cause personal injury or death. Avoid contacting the ignition system components and the ignition system wiring during operation.
Use the electronic service tool in order to perform the "ARD Ignition Test".Note: The ARD Ignition Test cannot be performed if the DPF soot loading is above 80%. When the DPF soot loading is above 80%, use the electronic service tool to perform a Manual DPF Regeneration.Results:
The "ARD Ignition Test" was successful and no codes were logged. - Return the unit to service.STOP
The "ARD Ignition Test" was not successful and a 3556-7 diagnostic code was logged. - Proceed to Test Step 2.
The "ARD Ignition Test" was not successful and another diagnostic code was logged. - Repair: Troubleshoot the other diagnostic codes. Refer to Troubleshooting, "Diagnostic Trouble Codes".STOPTest Step 2. Check the Current Flow Through the ARD Nozzle Heater
Turn the keyswitch to the OFF position.
Illustration 1 g02231813
Typical view of the ARD combustion head (1) Insulated part