P208BReductant Pump A Control Performance/Stuck Off
- 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
- P208B is the functional check of DEF pump A: the circuit is intact, yet the pump ignores its command or stays off. Ford, titling it Reductant Pump Control Range/Performance, sets it on 2023 diesels when pump speed misses its setpoint by over 300 rpm or its speed control sits at a limit for 30 s, detected within 5 s and only after the circuit tests have passed. GM's 2014 diesel table reports Reductant Pump Performance when the pump motor's functional acknowledgement takes longer than 4 s, Type B. Deutz EMR5 adds an overheated output stage (P208B-4B) and an abnormal rate of change (P208B-92). In the field the hydraulics are usually to blame: FCA STAR S1925000008 (Grand Cherokee, Wrangler diesel) names trapped air in the tank filter and external leaks, and a Volkswagen 2.0 TDI tip rules out leaking lines first.
- What you may notice
- MIL with DEF system message, often with P20E8
- White urea crust on lines or fittings
- Countdown to no-restart or reduced power
- Likely causes
- LikelyAir trapped in the tank filter or suction side after service
- LikelyLeaking DEF line or connection between pump and dosing valve
- PossibleWorn, frozen or crystallised pump
- RareCalibration needing an update (FCA 3.0L diesel)
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €50 – €1,800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.