P2002

• Check engine light, sometimes the DPF warning light
• Black smoke when accelerating (if the filter is holed)
• Failing the emissions test at inspection
• Usually no loss of power while driving

• Cracked DPF ceramic body, or melting from excessive regeneration
• Differential pressure sensor hoses disconnected, holed or fitted the wrong way round
• Faulty differential pressure sensor (low signal)
• DPF emptied without the software being switched off
• Exhaust leak before the DPF

1. Check the differential pressure sensor hoses and pipes; make sure inlet and outlet are the right way round.
2. Watch differential pressure in live data: a healthy DPF reads a few mbar at idle and around 50–150 mbar at 3000 rpm; if it stays near 0 the DPF is holed or empty.
3. Check the end of the tailpipe; if the inside is coated with soot, the DPF is letting soot through.
4. Test whether the differential pressure sensor reads close to 0 mbar with the ignition on.
5. If needed, remove the DPF and inspect the inside with a light test or endoscope.

1. If it's a hose or sensor fault, replace it and reset the sensor adaptation.
2. If the DPF is damaged, fit a new or remanufactured DPF.
3. After replacement, run the DPF replacement/soot mass reset in the ECU.
4. Also fix the injector or oil-burning problem that caused the melting.

• P2003Particulate Trap Efficiency Below Threshold
• P200CParticulate Filter Over Temperature Bank 1
• P200DParticulate Filter Over Temperature Bank 2

This page is general information; an exact diagnosis needs measurements and a technician’s check.