Powertrain, generic (extended)

P2003 Diesel Particulate Filter Efficiency Below Threshold (Bank 2)

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P2003 is set when the particulate filter of bank 2 lets too much soot slip through, which almost always points to a cracked, partly melted, hollowed-out or bypassed core. Separate filters per bank are uncommon, so the code is rare. No manufacturer documents P2003 publicly; GM and Ford explain the detection under the bank 1 code P2002: older systems judge the flow resistance of a freshly regenerated filter, newer ones use a resistive PM sensor behind it, which signals too early when soot gets past the filter. CARB requires the system to catch a filter whose leakage pushes PM beyond the limit and also one whose substrate is missing. A forced regeneration will not cure a broken filter; it has to be replaced. The warning lamp may be the only sign, with soot at the tailpipe if the leak is large.

Likely causes

Bank 2 filter core cracked or melted after an overheated regeneration
Filter on bank 2 removed, emptied or bypassed
PM sensor or differential pressure measurement on bank 2 giving false values

Symptoms

  • Malfunction indicator lamp on
  • Visible soot at the tailpipe with a large leak
  • Engine performance normally unaffected

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–3,500
Time0.5–4 h

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

Parts involved

diesel particulate filterparticulate matter sensordpf differential pressure sensor

Related codes

P2002P2465P24AF

References: law.cornell.edu, gsi.ext.gm.com, en.wikipedia.org.