The P2003: Diesel Particulate Filter Efficiency Below Threshold Bank 2 indicates that the Diesel Particulate Filter (DPF) on Bank 2 is not performing efficiently in reducing soot emissions. This could be caused by a clogged DPF, a faulty filter sensor, or engine performance issues affecting the filter’s functionality.
P2003 – Quick Overview
Code | Information |
---|---|
Meaning | P2003: Diesel Particulate Filter Efficiency Below Threshold Bank 2 |
Is it serious? | Yes, a clogged DPF can result in higher emissions and reduced engine performance, potentially leading to further engine damage if left unresolved. |
Possible causes | – Clogged diesel particulate filter – Faulty filter sensor – Engine performance issues |
How to diagnose? | – Inspect and test the diesel particulate filter – Check filter sensor functionality – Assess engine performance and emissions |
P2003 Meaning
The P2003: Diesel Particulate Filter Efficiency Below Threshold Bank 2 code signals that the DPF in Bank 2 is not effectively capturing and reducing particulate matter (soot) emissions from the exhaust system. A clogged or failing DPF can reduce exhaust flow, leading to increased emissions, poor engine performance, or potential damage to the engine or turbocharger system.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for additional fault codes related to exhaust or emission system problems. These codes may help in diagnosing the underlying issue. | OBD-II Scanner |
Inspect the Diesel Particulate Filter (DPF) | Visually inspect the DPF on Bank 2 for signs of clogging or damage. If the filter is clogged with soot or ash, it may need cleaning or replacement. | Flashlight, DPF Tester |
Test the Filter Sensor | Use a diagnostic tool to test the functionality of the filter sensor. The sensor monitors the pressure differential across the DPF to detect blockages or reduced efficiency. | Diagnostic Tool, Multimeter |
Assess Engine Performance | Evaluate engine performance by checking for excessive smoke, reduced power, or other performance-related issues that may indicate a problem with exhaust flow or emissions control. | Diagnostic Tool, Emissions Tester |
Check for Exhaust Leaks | Inspect the exhaust system for leaks or damage that could affect the DPF’s efficiency or lead to erroneous readings from the sensors. | Flashlight, Smoke Machine |
Clear the Code and Test Drive | After completing any necessary repairs or cleaning, clear the P2003 code using an OBD-II scanner. Perform a test drive to verify that the issue has been resolved and that the DPF is functioning properly. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the vehicle to ensure the P2003 code has not reappeared. | OBD-II Scanner |

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Hi, I am Juraj “Yuri” Lukacko. I got frustrated by unhelpful and scammy mechanics, so I decided to learn everything about car diagnostics myself. I test dozens of new car diagnostic tools every month along with learning new strategies to fix and customize cars. About Juraj Lukacko (Yuri)