P2BA7NOx Exceedence - Empty Reagent Tank
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2BA7 records that NOx control has been lost because the DEF or AdBlue tank has run dry, so no reagent can be dosed. Regulation (EU) 2017/1151 Annex XVI requires a level warning no later than 2,400 km ahead of an empty tank and an inducement that keeps the vehicle from operating with an empty tank, typically by blocking the next engine start after a countdown. CARB 13 CCR 1968.2 (f)(2.2.3)(B) asks for an empty-reagent diagnosis but exempts makers whose inducement prevents running dry. Ford lists P2BA7 in its 2014 code interpretation table; no public document gives a threshold. The normal level code is P203F; P2BA7 is the consequence once the tank is empty. Refilling with enough fluid usually clears warning and limits.
- What you may notice
- DEF empty message with restart countdown
- Engine will not restart once countdown expires
- MIL or emission warning on
- Likely causes
- LikelyDEF tank simply not refilled despite level warnings
- PossibleLevel sensor reading empty although fluid is present (fault, ice, deposits)
- RareLeaking DEF tank or line emptying the system
- RareOnly a small amount refilled, below the quantity the system needs to recognise a refill
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Easy · Often possible to do yourself.Typical cost: €10 – €300
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.