This article covers Mercedes C Class DPF Blocking and Regeneration, Symptoms and Cleaning, Fault Codes, and How Long Does It Take to Replace a DPF. When attempting to repair a blocked DPF, regeneration is one method to consider, however it does not always effective.
Mercedes C Class DPF Blocked Problems. In this blog, we discuss Mercedes C Class DPF Blocking and DPF Regeneration, Symptoms and Cleaning, Fault Codes and How Long it Would Take to Replace a DPF. For technical assistance regarding Mercedes C Class (DPF Block) please call 0330 043 4921 . All chemicals are professional grade and should be used with a specialist machine. For more information, you can contact us at. Regeneration is one option to try when trying to fix a blocked DPF. However, this may not always work. A professional clean or replacement will be needed.
Mercedes C Class DPF Blocked Problems. In this blog, we discuss Mercedes C Class DPF Blocking and DPF Regeneration, Symptoms and Cleaning, Fault Codes and How Long it Would Take to Replace a DPF. For technical assistance regarding Mercedes C Class (DPF Block) please call 0330 043 4921 . All chemicals are professional grade and should be used with a specialist machine. For more information, you can contact us at. Regeneration is one option to try when trying to fix a blocked DPF. However, this may not always work. A professional clean or replacement will be needed.
Identify the symptoms and determine if your DPF has a fault ….
Signs that your DPF is blocked
- Limp mode
- It is difficult to get started
- Bad smells
- Power loss
Next, you can try DPF regeneration ….
Mercedes C Class DPF Regeneration process
- Make sure the engine is running at the correct temperature
- For at least 25 minutes, drive the vehicle at 50mph or less
- When regeneration is complete, the warning message will end
Third step…
You can have your DPF professionally cleaned by GEL Automotive. We have a fleet nationwide of mobile vans that offer a service that includes diagnostics and cleaning. This is without removing your DPF. Our mobile DPF Assist vans are equipped with the latest technology to do this at your home or work when and where possible.
The benefits of our DPF cleaning technology:
Removal of all residuals including PM10 particles and cerium.Efficient cleaning of all of the types of particulate filter and catalyst.Preservation of the noble metal coatings of the DPF and catalyst.Environmentally friendly process.
We have compiled a troubleshooting guide for common mercedes DPF Fault codes if you have a scanner that can diagnose your device.
GEL Automotive Fault Finding Guide (DPF) Mercedes DPF fault codes
| Fault Code | Code for Causes of Fault |
|---|---|
| P2002 DPF efficiency lower than threshold bank 1 | Short distance driving |
| Below threshold efficiency of P2003 DPF | A sensor reading will fluctuate due to an air leak, which will trigger the codes These fault codes will be caused by fuel with high levels of Sulphur |
| P0470 Pressure sensor failure | Pipe obstruction from the sensor to exhaust |
| P0471 Exhaust pressure sensor range/performance | EGR valve /air leaks |
| If left untreated, P242f | Sensor for exhaust pressure is not working properly |
| Circuit for P2031 exhaust gas temperature sensor Low P2032 exhaust gas temperature sensor High-temperature P2033 exhaust gas temperature sensor | Connectors and terminals that are loose or corroded Broken wires Sensor fault |
| P242f Ash accumulation restriction | DPF ash accumulation excessive Defective DPF pressure sensor DPF pressure sensor pipes/hoses clogged Circuit/s that are either shorted or open in the DPF sensor circuit Inefficient DPF regeneration Excessive use of engine or fuel system components Inoperative DPF regeneration system |
| P244a DPF differential pressure too low Too high differential pressure for P244b DPF | Insufficient/incorrect diesel exhaust fluid DPF Pressure Sensor – Open or Shorted Circuit Defective ECU programming Defective DPF sensor Faulty DPF |
| P2458 DPF regeneration duration P2459 DPF regeneration frequency | Sensor for exhaust pressure is not working properly Insufficient/incorrect diesel exhaust fluid Open or shorted wiring to the DPF injection pump system Faulty DPF DPF pressure sensor circuit: Open or shorted Pressure sensor for DPF is not working properly The diesel exhaust fluid reservoir might be empty Improper diesel exhaust fluid |
| P2455 DPF pressure sensor circuit a high | Leakage of exhaust Blockage of DPF pressure sensor tubes/pipes due to blockage |
| P2463 DPF restriction | Inoperative active DPF regeneration system Incorrect installation or replacement of DPF Clearance of error codes from the past is not correct |
| P2454 DPF pressure sensor a circuit low | Insufficient DPF regeneration results in excessive soot accumulation Insufficient/incorrect diesel exhaust fluid Sensor for exhaust pressure is not working properly |
| P2452/53 DPF pressure sensor a circuit range/performance | The diesel exhaust fluid reservoir has been empty (AdBlue). Incorrect diesel exhaust fluid Defective DPF pressure sensor DPF pressure sensor pipes/hoses clogged Pressure sensor: Open or shorted circuit Inefficient DPF regeneration |
Test the pressure sensor
It varies between the bulkhead, underneath the bonnet or under the DPF. The connector plugs into the sensor via 3 wires.
- Constant 5.0 Volt
- Earth wire
- Trigger ECU wire measuring volts
You can test the sensor using either a multimeter or diagnostic equipment via live data stream. Measure the voltage at idle engine.
- 0.4-0.5 on engine idle
- 0.5 to 0.7 at 2000 rpm revs
- 0.7-0.9 at 3000 rpm or more
If one of these voltage readings is wrong, it means that the pressure sensor needs to be replaced. If you have to replace the DPF on your Mercedes C Class model, the fitting time is 2.65 hours if it’s done by an engineer.