Particulate Filter Efficiency Below Threshold Bank 2
What it means
P2003 means the diesel particulate filter on bank 2 is not trapping soot as effectively as required. It is usually caused by a filter that cannot complete regeneration — often from short, low-speed driving — or by a faulty pressure sensor giving a false reading. The engine still runs, but the vehicle may cut power or force regenerations until the filter is cleaned or replaced.
Can I keep driving? Driveable, but the vehicle may limit power or force regenerations — address it before the filter clogs enough to trigger a derate.
Real-world scan data
Appears alongside · share of P2003 scans
Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.
Common symptoms
What you'll notice
- Check-engine light on
- Reduced power or a limited-performance (derate) mode
- More frequent diesel particulate filter regenerations
- Possible increased exhaust smoke or diesel smell
Common causes
Most likely first
- Filter clogged from mostly short-trip, low-speed driving that prevents full regenerationLikely
- Damaged or degraded particulate filter (cracked substrate or failed coating)Common
- Faulty DPF differential-pressure sensor or blocked pressure hoses giving a false readingCommon
- Exhaust leak upstream of the filterLess often
- Poor-quality or high-sulphur fuel fouling the filterLess often
- Faulty engine control module (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and check the DPF differential-pressure sensor reading and hoses.
- Attempt a full regeneration — a sustained highway drive or a forced regen with a scan tool.
- Inspect for exhaust leaks ahead of the filter and repair any found.
- Use the correct low-sulphur diesel and verify no wrong fuel was used.
- Replace the particulate filter if it is cracked, melted, or too clogged to regenerate.
FAQ
Quick answers
Is it safe to drive with P2003?+
Can I just clear P2003?+
Related codes
Read & clear P2003 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.