Fault-Code Library · DPF / emissions
P242F: Diesel particulate filter ash accumulation
The ECU has calculated excessive ash or restriction in the diesel particulate filter.
Common symptoms
- •DPF warning
- •Reduced power
- •Failed regeneration
- •High exhaust backpressure
Likely causes
- •High ash load
- •Long service life
- •Oil consumption
- •Previous regeneration or sensor faults ignored
First checks
- •Read calculated ash and soot values
- •Check differential pressure
- •Review regeneration history and oil-consumption evidence
Important
Ash loading is not the same as soot loading; forced regeneration cannot remove ash from a full DPF.
A fault code identifies a detected condition, not a failed part. Confirm manufacturer-specific subcodes and live data.
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