P20D2Exhaust Aftertreatment Fuel Injector B Control Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- With its wiring intact, the second exhaust fuel doser (B) is not delivering what was asked for: too little heat appears across the catalyst during dosing, or heat appears when it should be idle. No manufacturer documents P20D2 publicly. The comparable check for injector A on GM's 6.6 L Duramax (P20CC, 15OBDG09) watches for the catalyst outlet running far hotter than its inlet outside regeneration. CARB requires a malfunction whenever the injection system can no longer bring about regeneration, and a feedback-control fault if the system runs out of adjustment. Stuck positions of doser B are P20D5 and P20D6, the electrical faults P20D1, P20D3 and P20D4.
- What you may notice
- Check engine light on
- Longer or more frequent regenerations
- Higher fuel consumption
- Likely causes
- LikelyPartly coked nozzle on doser B
- PossibleLow or unstable fuel pressure feeding doser B
- RareExhaust temperature sensor reading wrong
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €300 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.