P246C
Particulate Filter Restriction - Forced Limited Power Bank 1
Diesel particulate filter
Generic OBD-II
High
What it means
P246C means the diesel particulate filter is so restricted with soot that the ECU has forced the engine into limited (reduced) power to protect it. It's the serious end of the DPF codes: the filter needs a successful regeneration or a service clean before it saturates with ash and requires replacement.
High
Can I keep driving? The ECU has already cut power to protect a badly clogged filter. Drive gently to a shop soon — ignoring it risks a very expensive DPF replacement.
Common symptoms
What you'll notice
- Noticeable loss of power / limp mode
- Check-engine light on, often with a DPF warning light
- Repeated or failed regeneration attempts
- Higher fuel use and exhaust smell
Common causes
Most likely first
- Diesel particulate filter heavily loaded with soot from short-trip or low-speed drivingLikely
- Regeneration repeatedly aborted or never completingCommon
- Faulty DPF pressure or exhaust-gas-temperature sensor misreading filter loadCommon
- Fuel injector, EGR, or turbo fault raising soot outputLess often
- Physically damaged or ash-saturated DPF near end of lifeLess often
How to diagnose & fix
Work through it in order
- Scan for companion codes (P2002, P2458, P2459, P2463) and check freeze-frame for what triggered the restriction.
- Verify the DPF differential-pressure and EGT sensors read correctly before assuming the filter is bad.
- Attempt a scan-tool forced regeneration if soot load is within limits; otherwise a service regen is needed.
- Address any soot source — leaking injectors, EGR faults, boost leaks — so it doesn't reclog.
- If soot/ash load is too high to burn off, clean or replace the filter, then reset the load counters and re-test.
FAQ
Quick answers
Is it safe to drive with P246C?+
Only gently and only to get it repaired. The vehicle is already in reduced power to protect the filter; continued hard driving can push the DPF past cleaning and into replacement.
Can I just clear P246C?+
No. The filter is physically restricted. Clearing the code won't remove the soot — it returns immediately until a successful regen or filter service is done.
Related codes
Often seen with P246C
Read & clear P246C 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