Applicable Systems
EMCP 4.2
Symptoms
DPF restriction warning; engine derate active; soot loading above regeneration threshold.
Possible Causes
- DPF soot accumulation exceeding active regen threshold
- Exhaust backpressure sensor faulty
- DPF substrate partial blockage
Troubleshooting Steps
- Step 1: Check DPF soot loading via Cat ET
Soot loading < 100% before regen needed - Step 2: Initiate stationary DPF regeneration via Cat ET
Regen completes, soot load < 30% - Step 3: Inspect DPF differential pressure sensor
Sensor reading matches mechanical gauge - Step 4: Check exhaust system for leaks before DPF
No exhaust leaks found - Step 5: Clear code and verify DPF pressure within spec
DPF diff pressure < 3 kPa at idle
How to Reset
Clear via Cat ET after successful DPF regeneration.
Common Replacement Parts
- DPF Differential Pressure Sensor P/N: 368-8531
Frequently Asked Questions
- Q: How often should DPF regeneration occur?
Active regen typically every 50-100 hours depending on load cycle. Stationary regen when soot load reaches threshold.
Source: verizonconnect.com DTC guide
Category: Heavy Equipment