C7.1 Industrial Engine and Generator Set Caterpillar

ARD Is Disabled

Usage:

C7.1 770

Use this procedure in order to troubleshoot a failed Diesel Particulate Filter (DPF) regeneration. Also, use this procedure if one of the following diagnostic trouble codes are active.

Show/hide table

Table 1
Diagnostic Trouble Codes That Cause the ARD to Be Disabled
J1939 Code	Code Description	Comments
3750-31	Diesel Particulate Filter 1 Conditions Not Met for Active Regeneration	The diesel particulate filter is not able to perform an active regeneration at the current engine operating conditions.
3703-31	Particulate Trap Active Regeneration Inhibited Due to Inhibit Switch	The regeneration system is disabled by the "ARD Disable" switch.

Check for Diagnostic Codes that are Active
1. Connect the electronic service tool to the diagnostic connector.
1. Turn the keyswitch to the On position.
1. Download the following items before performing any troubleshooting or clearing any diagnostic codes:
  - Warranty Report
  - Aftertreatment Regeneration Trigger History
  - Product Status Report with Histograms
1. Monitor the active diagnostic code screen on the electronic service tool. Check and record any diagnostic codes that are active or logged. Look for the following diagnostic codes:
  Note: Wait at least 30 seconds in order for the diagnostic codes to become active.
  - 3750-31
  - 3703-31
1. Remove the electrical power from the ECM.
1. If a 3750-31 diagnostic code is present, proceed to Step 2.
1. If a 3703-31 diagnostic code is present, proceed to Step 3.

A 3750-31 Diagnostic Code is Present.
1. The operator did not allow enough time at a suitable engine speed and load for regeneration to occur. The operator must respond when the DPF lamp is illuminated. Once the DPF and action lamps are illuminated, the engine must be operated at a reduced load until the soot load is reduced to 50 percent.
1. Refer to the Operation and Maintenance Manual, "Monitoring System (Aftertreatment Regeneration Device)" for the correct operation of the regeneration system.
1. Return the unit to service.

A 3703-31 Diagnostic Code is Present.
1. The operator has disabled the regeneration system by moving the "ARD Disable" switch to the Stop position. Move the "ARD Disable" switch to the Start position in order to perform a regeneration.
1. Refer to the Operation and Maintenance Manual, "Monitoring System (Aftertreatment Regeneration Device)" for the correct operation of the regeneration system.
1. Return the unit to service.