Diesel particulate filter (DPF) light on: what to do
Updated:
The DPF light means the diesel particulate filter is full of soot and needs to burn it off. If the car pulls normally, do a regeneration drive: about 15–30 minutes of steady driving on a main road, usually at a constant speed with the engine at about 2000 rpm or more (the exact conditions depend on the manufacturer). If the light stays on, power drops or the check engine light comes on too, bring the car in before the filter blocks completely.
Why the filter clogs
The filter collects soot and burns it off now and then. That needs a very hot exhaust. On short town trips, especially in winter, the burn never finishes.
A faulty EGR valve, injectors, a turbo oil leak and the wrong engine oil speed it up. A diesel with a DPF needs low-ash oil that meets the manufacturer's spec.
How to do a regeneration drive
Drive steadily for about 15–30 minutes on a main road, usually at a constant speed with the engine at about 2000 rpm or more. The exact conditions depend on the manufacturer, so check the handbook. Don't switch off during that time. While a burn is running, the cooling fan may keep running after you stop and the idle may be slightly higher; that's normal.
If the light goes out, all is well. If it stays on or soon comes back, the cause needs finding.
What the codes say
P2002 means filter efficiency is below threshold. P2463 means too much soot in the filter. P2452 and similar codes point to the pressure sensor, which can read wrong while the filter is fine.
In the workshop we check soot load and pressure, test the sensor and its hoses, and start a forced regeneration with a diagnostic tool if needed. A filter full of ash or damaged inside has to be cleaned or replaced.
Want a definite answer?
Bring the car to our workshop in Estonia for diagnostics. We read the fault codes, test the sensors and tell you what is wrong.
Frequently asked questions
Can you drive with the DPF light on?
If the car pulls normally, yes, and do a regeneration drive straight away. If power drops or the car goes into reduced power mode, don't drive far.
DPF light or check engine light: what is the difference?
The DPF light says the filter is full and needs a burn. If the check engine light comes on too, a fault code is stored and it's worth coming in straight away.
Can a DPF be cleaned?
Usually yes. It needs replacing when damaged inside or full of ash.
Can the DPF be removed?
No. Removing it is illegal and the car will fail the inspection. We don't do that work.
How much does a diagnosis cost?
Diagnostics cost €45/h, the price depends on the job. You can book a visit on this page.