GEAR-PLANETARY 7G3451 - Caterpillar

The Electronic Control Module (ECM) calculates the amount of ash that is in the Diesel Particulate Filter (DPF). The ECM activates the following code when the conditions are met.
Table 1
Diagnostic Trouble Codes For High Ash Load    
J1939 Code    Code Description    Comments    
3720-15     Particulate Trap #1 Ash Load Percent : High - least severe     The ECM has determined that an ash service is required. The calculation is based on the size of the DPF and the operating hours for the engine.
Once the ash service has been completed, the electronic service tool can be used in order to reset the parameter in the ECM.    
3720-16     Particulate Trap #1 Ash Load Percent : High - moderate severity     The ECM has determined that an ash service is required. The calculation is based on the size of the DPF, the operating hours for the engine and the duty cycle for the engine.
Once the ash service has been completed, the electronic service tool can be used in order to reset the parameter in the ECM.    
Follow the troubleshooting procedure in order to identify the root cause of the fault.    Note: Download the following items before performing any troubleshooting or clearing any diagnostic codes:
Warranty Report
Aftertreatment Regeneration Trigger History
Product Status Report with HistogramsWhen a 3720-15 code or a 3720-16 code are active, the DPF requires an ash service. For further information, consult a Caterpillar dealer.