P2003
Particulate Filter Efficiency Below Threshold Bank 2
Diesel particulate filter (emissions)
Generic OBD-II
Medium
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.
Medium
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.
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?+
For a while, yes, but keep it brief. Short low-speed trips make it worse; a longer highway drive may let the filter regenerate and clear the condition.
Can I just clear P2003?+
Clearing it without a successful regeneration or repair only masks a filling filter — it will return and can escalate to a power derate.
Related codes
Often seen with P2003
Read & clear P2003 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX