P246C fault code meaning and fix
P246C means the diesel particulate filter is so restricted that the engine computer has deliberately cut power. It usually follows a soot build-up that wasn't cleared in time, and we can take readings and clean the filter where the vehicle is parked.
The short answer
The official description is DPF restriction, forced limited power. The filter's soot load or back pressure has passed the point where the ECU will let the engine run at full power, so it holds performance down to protect the filter and turbo.
Keep any journeys short and gentle until it's sorted, because the power limit won't lift on its own. A regeneration at this soot level carries a risk of cracking the filter, so don't try to force one with a long hard run.
Symptoms that go with P246C
- Power held right down, with the engine refusing to rev freely
- A DPF light, often with the engine management light
- P2463 stored as well, from the earlier soot warning
- Regenerations that start but never finish
- A strong hot smell from the exhaust after use
What causes P246C
| Cause | What you might notice | How it's confirmed |
|---|---|---|
| Soot build-up from short trips | DPF light ignored for a while before power dropped | Soot load and pressure readings |
| Regenerations interrupted again and again | Fan running on, then the engine switched off mid-regen | Regeneration history on live data |
| Engine making extra soot | Black smoke, a sticking EGR valve or injector fault | Related codes and live engine data |
| Ash in an older filter | High pressure even after a regeneration | Ash estimate, often with P242F |
| Faulty pressure sensor or pipes | Power cut with a soot figure that doesn't add up | Sensor figures checked against the filter |
Reading P246C properly
P246C is the step after P2463. Many vehicles log P2463 when soot passes the first limit, then add P246C once it goes high enough to justify cutting power, which is why the two are often searched together for the Ford Transit.
Since P246C describes the outcome, the readings decide the fix. A high soot figure points to cleaning, while a high ash figure or a sensor that disagrees with the soot model points somewhere else.
How P246C gets fixed
Take readings first
Soot load, ash estimate and DPF pressure are read before any work starts.
Clean if it's soot
A cleaning solution goes into the filter, then a forced regeneration burns off the loosened soot with the filter left in place.
Find the reason it filled up
Short trips, a sticking EGR valve or a sensor fault are checked so it doesn't happen again.
Clear and recheck
Codes are cleared and the pressure across the filter is checked to confirm it's back to normal.
What we can do about P246C
DPF cleaning, £275 + VAT
Readings first, then a cleaning solution and a forced regeneration on site, with codes cleared at the end. If the filter is beyond cleaning, you're told before any work starts.
Mobile diagnostics, £100 + VAT
If the readings don't point to soot, a full diagnostic finds out whether ash, a sensor or an engine fault is behind it.
DPF delete, £220 + VAT
For Transit and Ranger models with the locked SID212 ECU, see our SID212 DPF delete page.
What does P246C mean in plain English?
The DPF is so blocked that the engine has been put on a power limit until the filter is cleared.
Is P246C a serious fault?
Yes. It's the ECU's last step before real damage. Leaving it risks a cracked filter or a strained turbo, and a cleaning job can become a new filter.
Can I clear P246C with a cheap code reader?
You may clear the light, but the soot is still there and the power limit comes straight back. Most cheap readers can't run a forced regeneration either.
Does P246C mean the same thing on every make?
It's a generic code, though it turns up most in searches alongside P2463 on Ford vans. Every make that uses it is telling you the same thing about a restricted filter.
How much does it cost to find the cause of P246C?
If the readings show soot, a DPF clean at £275 + VAT deals with it on the spot. Where something else is behind it, diagnostics is £100 + VAT.
Can I have the DPF deleted instead and keep driving on the road?
No. A DPF delete is for off-road and export vehicles only, as Is DPF removal legal? explains.
Get your P246C fault checked
Send the registration and tell us how long the power has been down, and we'll bring the readings and cleaning kit to the vehicle.
More fault codes explained
Eccles, Manchester M30 0SF