DIFFERENTIAL GP 4896966 - Caterpillar

Table 1
Troubleshooting Test Steps     Values     Results    
1. Check the Regeneration History
A. Connect Cat® Electronic Technician (ET) to the service tool connector.
B. Open the "Information" tab.
C. Open the "History" tab.
D. Open the "Aftertreatment Regeneration History" tab.
E. Verify the following information:
1. If the regeneration intervals have changed
2. If the regeneration was manual or automatic
3. The soot level when the regenerations occurred.
   
Regeneration History    
Result: The engine has logged 5000 hours since the last ash service regeneration
Repair: Perform an ash service.
Refer to Special Instruction, REHS8180, "Aftertreatment Filter Maintenance on Tier 4 Final Products Equipped with a Diesel Particulate Filter (DPF), Diesel Oxidation Catalyst (DOC) and a Selective Catalyst Reduction (SCR) Filter".
Result: The engine has logged less than 5000 hours since the last ash service regeneration
Proceed to Test Step 2.
   
Illustration 1 g03755617
Illustration 2 g03429630
Table 2
Troubleshooting Test Steps     Values     Results    
2. Inspect for Restrictions
A. Remove the DPF Differential Pressure sensor and lines group.
B. Closely inspect the sensors, elbows, lines, and manifold for restrictions. Restrictions could be caused by an accumulation of moisture, ice, or soot.
   
Restrictions    
Result: Restrictions were found.
Repair: Replace the affected components. Perform a Manual DPF Regeneration using Cat ET to verify that the problem is resolved.
Result: Restrictions were not found.
Proceed to Test Step 3.
   
3. Perform an "EGR System Test"
A. Start the engine.
B. Perform an "EGR System Test" using Cat ET.
    "EGR System Test"    
Result: The "EGR System Test" failed.
Repair: Proceed to Troubleshooting, "NOx Reduction System (NRS) - Test" to troubleshoot the EGR system.