Powertrain, generic (extended)

P243C Particulate Filter Regeneration Frequency (Bank 2)

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P243C is stored when the bank 2 particulate filter needs regeneration more often than its calibration allows. CARB requires diesel OBD to recognise regeneration so frequent that emissions would rise above the limit. No manufacturer documents this bank 2 code publicly, so the bank 1 code P2459 serves as the reference: Ford's 2023 diesels flag it once completed regenerations occur, on average, less than roughly 40 km apart. Excess soot from the engine side of that bank, for example a leaking injector, an EGR or boost fault, or a pressure reading that overstates the load, makes the filter look full too early. Every extra regeneration burns fuel and can thin the engine oil. If the other bank regenerates at normal intervals, compare what differs on this side.

Likely causes

Too much soot from bank 2 cylinders (injector, EGR or boost fault)
Pressure sensor or hose overstating the bank 2 soot load
Filter partly filled with ash, leaving little soot capacity

Symptoms

  • Regeneration running unusually often
  • Higher fuel consumption, rising oil level
  • MIL on

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–3,000
Time1–5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

dpf b2fuel injectors

Related codes

P2459P243DP243EP24A3

References: law.cornell.edu, fordservicecontent.com.