BMW Diesel Particulate Filter (DPF) Reset
Supported coding feature by BimCOM diagnostic tool https://www.obdtester.com/bimcom
DPF Reset (After Replacement or Cleaning)
What it does
- Resets the calculated soot load values in the engine control unit
- Clears DPF ash accumulation counters
- Initializes new baseline values for a replaced or professionally cleaned filter
- Ensures correct regeneration scheduling based on fresh DPF data
Why the reset is required
- The ECU monitors:
- Soot mass (dynamic value)
- Ash mass (long-term value)
- Exhaust backpressure trends
- After installing a new or cleaned DPF:
- Old soot/ash values remain stored
- Regeneration may be triggered too early or not at all
- The system may falsely detect a clogged DPF
Conditions that must be met before the reset
- DPF must be:
- Brand new OR professionally cleaned
- Correctly installed with all sensors reconnected
- No exhaust leaks upstream of the DPF
- No active DPF-related fault codes (pressure sensor, temperature sensors, glow system)
- Differential pressure sensor must be functional and reading correctly
- Engine at normal operating temperature recommended
- Stable electrical system voltage (external charger preferred)
When the reset should be performed
- Replacement of the DPF with a new unit
- Cleaning of the original DPF (ultrasonic, hydrodynamic, or chemical process)
- Replacement of the differential pressure sensor (optional but recommended)
- ECU displays incorrect soot load values after repairs
- After fixing exhaust backpressure or temperature sensor faults
What happens during the procedure
- ECU resets internal counters:
- Soot mass to baseline
- Ash mass to factory value
- Regeneration history
- Adapts pressure sensor reference values
- Sets new exhaust flow characteristics for the fresh DPF
- Clears learned backpressure curves
If the reset is not performed
- Incorrect soot load estimation
- Regenerations may:
- Occur too frequently
- Not occur at all
- Trigger limp mode
- Increased fuel consumption
- Higher exhaust backpressure and risk of turbocharger strain
- Possible DPF efficiency and pressure-related fault codes
After the reset
- Perform a test drive to allow ECU to relearn pressure values
- Monitor live data for:
- Differential pressure
- Regeneration status
- Exhaust temperatures
- Ensure no new fault codes appear
- Regeneration should resume automatically under normal driving conditions