99101-GHB-1020 Honda JET, MAIN (#102) (Honda Code 4636098).

Table 1
Diagnostic Trouble Codes for ARD Failed to Ignite    
J1939 Code     Code Description     Comments    
3473-31     Aftertreatment #1 Failed to Ignite     The ARD has failed to ignite for a regeneration cycle or the ARD failed to ignite during an ARD Ignition Test. Usually, this code is accompanied by another logged code that indicates the condition that caused the failure to ignite.    System OperationThe combustion air system routes pressurized air from the outlet of the high-pressure turbocharger to the ARD. The combustion air is mixed with fuel inside the ARD combustion head. The air/fuel mixture is ignited and the air/fuel mixture is burned in order to increase the temperature of the exhaust gas. The high temperature exhaust gas burns off the soot in the Diesel Particulate Filter (DPF). This process is known as DPF regeneration.The ECM sends a pulse width modulated signal to the combustion air valve. The actuator in the combustion air valve regulates the combustion air to the ARD combustion head.The ECM also sends pulse width modulated signals to the pilot fuel control valve. The pilot fuel control valve regulates the amount of fuel that is injected into the ARD combustion head.The ECM controls the ARD ignition system. Whenever the ARD is required to operate, the ECM operates the ARD ignition coil which then generates high voltage pulses in the ignition cable. The high voltage pulses create sparks at the spark plug in the ARD head. The spark ignites the fuel/air mixture in the ARD.If the amount of fuel or air that enters the ARD combustion head is incorrect or there are no ignition sparks, combustion may not occur.Test Step 1. Check for Associated Diagnostic Trouble Codes
Establish communication between the electronic service tool and the engine ECM.
Download the following items before performing any troubleshooting or clearing any diagnostic codes:
Warranty Report
Aftertreatment Regeneration Trigger History
Product Status Report with Histograms
Use the electronic service tool to check for active diagnostic codes.
Table 2 lists the diagnostic trouble codes that are associated with the "3473-31 Aftertreatment #1 Failed to Ignite" code. Determine if any of the codes in Table 2 are present.
Table 2
Associated Diagnostic Codes    
J1939 Code     Description     Associated Diagnostic Procedure    
3487-7     Aftertreatment #1 Air Pressure Control : Not Responding Properly     Motorized Valve - Test    
3480-16     Aftertreatment #1 Fuel Pressure #1 : High - Moderate Severity (2)     ARD Pilot Fuel Pressure Is High    
3480-17     Aftertreatment #1 Fuel Pressure #1 : Low - Least Severe (1)     ARD Pilot Fuel Pressure Is Low    
3480-18     Aftertreatment #1 Fuel Pressure #1 : Low - Moderate Severity (2)     ARD Pilot Fuel Pressure Is Low    
102-18     Engine Intake Manifold #1 Pressure Low (2)     Intake Manifold Air Pressure Is Low    
3556-7     Aftertreatment Fuel Injector #1 : Not Responding Properly     ARD Nozzle - Test    
3484-5     Aftertreatment #1 Ignition : Current Below Normal     ARD Ignition - Test    
3484-6     Aftertreatment #1 Ignition : Current Above Normal     ARD Ignition - Test    
4265-5     Aftertreatment #1 Transformer Secondary Output : Current Below Normal     ARD Ignition - Test    
4265-6     Aftertreatment #1 Transformer Secondary Output : Current Above Normal     ARD Ignition - Test    Results:
An associated diagnostic trouble code is not present. - Proceed to Test Step 2.
An associated diagnostic trouble code is present. - Repair: Refer to Troubleshooting, "Diagnostic Trouble Codes" in order to troubleshoot the associated diagnostic code.STOPTest Step 2. Inspect the ARD Ignition System
Visually inspect the components for the ARD ignition system. Check for the following faults:
Loose connections or damaged connectors
Moisture on the connectors or the wiring
Damage caused by excessive heat
Damage caused by chafing
Incorrect routing of wiring
Damaged insulation
Verify that each end of the ground wire is securely connected to both ground points.
Push the boot on each end of the ignition wire. There should not be a "click" when you push the boot onto either part. If a "click" is felt, the clip inside the boot was not connected.
Perform a 45 N (10 lb) pull test on each harness wire at the 3-pin connector for the ignition coil.Results:
The wiring is not OK. - There is a fault in the wiring. A wire end is not connected or a wire is damaged. Repair the wiring. If necessary, replace any damaged parts. Proceed to Test Step 9.
The wiring is OK. - Proceed to Test Step 3.Test Step 3. Check the Current Flow to the ARD Nozzle Heater
Verify that the engine is off.
Illustration 1 g02856716
Measuring the current flow (1) ARD combustion head (2) Metal part of heater wire (3) Insulated part of heater wire
Connect a suitable clamp-ammeter around the insulated part of the heater wire (3) . Make sure that the jaws of the ammeter are away from the metal part of the heater wire (2) .
Establish communication between the electronic service tool and the ECM. Refer to Troubleshooting, "Electronic Service Tools" for the proper procedure.
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.
Start the engine. Activate the "ARD Nozzle Heater Test".
Record the current reading on the ammeter.
Disable the "ARD Nozzle Heater Test". Stop the engine. Remove the clamp-ammeter.
Disconnect the electronic service tool.Results:
The ammeter reads at least 7 Amps for a 12 VDC system or 3.5 Amps for a 24 VDC system. - The current consumption is normal. Proceed to Test Step 4.
The ammeter reads less than 7 Amps for a 12 VDC system or 3.5 Amps for a 24 VDC system. - Repair: Investigate the cause of the low current consumption. Refer to Troubleshooting, "ARD Nozzle Heater - Test".STOPTest Step 4. Check for Voltage at the Spark Plug
Illustration 2 g02856717
368-6232 Spark Indicator (4) Connector for spark plug (5) Spark window (6) Connector for ignition wire