P2BAD on Peugeot
NOx Exceedance - SCR Catalyst Conversion Efficiency
P2BAD on Peugeot vehicles indicates nox exceedance - scr catalyst conversion efficiency. Au7o has documented this code across 2 Peugeot models — most commonly on 3008, 308. This code, found on modern diesels with selective catalytic reduction (SCR), means the system has detected that tailpipe NOx (nitrogen oxide) emissions have exceeded the legal limit because the SCR catalyst isn't converting them efficiently enough. The SCR system injects diesel exhaust fluid (DEF/AdBlue) over a catalyst to chemically break down NOx, and NOx sensors before and after the catalyst measure how well it's working. When the measured conversion falls below the required threshold, the computer flags this code, often triggering warning lights, a countdown to reduced power, or limp mode. Common roots are contaminated or low-quality DEF, a degraded catalyst, or faulty NOx sensors. Typical repair costs on Peugeot range from $300 to $1,200, depending on the specific model and root cause.
Common Causes of P2BAD
- •Contaminated, diluted, or low-quality diesel exhaust fluid (DEF)
- •Faulty NOx sensor (upstream or downstream)
- •Degraded, aged, or contaminated SCR catalyst
- •Faulty or clogged DEF/reductant injector
- •Insufficient DEF dosing or low DEF quantity
- •Exhaust leak before or within the SCR system
- •Faulty EGR system raising engine-out NOx
- •Wiring or connector faults to NOx sensors
P2BAD on Peugeot by Model
Peugeot 3008(1 issue)
- AdBlue System Malfunction2017-2026
The second-generation 3008 BlueHDi models are plagued by AdBlue system faults, including false level readings and crystallized injectors. The vehicle displays a countdown to engine disable even with a full AdBlue tank.
Peugeot 308(1 issue)
- AdBlue System Fault2014-2026
The AdBlue (SCR) system on BlueHDi engines triggers false fault warnings and countdown timers to engine disable. The NOx sensor and AdBlue injector are primary failure points, often caused by crystallized fluid.
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View P2BAD across all makes →Frequently Asked Questions
What does P2BAD mean on Peugeot?▼
P2BAD stands for "NOx Exceedance - SCR Catalyst Conversion Efficiency." This code, found on modern diesels with selective catalytic reduction (SCR), means the system has detected that tailpipe NOx (nitrogen oxide) emissions have exceeded the legal limit because the SCR catalyst isn't converting them efficiently enough. The SCR system injects diesel exhaust fluid (DEF/AdBlue) over a catalyst to chemically break down NOx, and NOx sensors before and after the catalyst measure how well it's working. When the measured conversion falls below the required threshold, the computer flags this code, often triggering warning lights, a countdown to reduced power, or limp mode. Common roots are contaminated or low-quality DEF, a degraded catalyst, or faulty NOx sensors. On Peugeot specifically, this code is documented across 2 models.
What causes P2BAD on Peugeot vehicles?▼
Common causes on Peugeot: Contaminated, diluted, or low-quality diesel exhaust fluid (DEF), Faulty NOx sensor (upstream or downstream), Degraded, aged, or contaminated SCR catalyst, Faulty or clogged DEF/reductant injector, Insufficient DEF dosing or low DEF quantity. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P2BAD on a Peugeot?▼
Repair costs on Peugeot range from $300 to $1,200, depending on the specific model and root cause.
Which Peugeot models have P2BAD documented?▼
Au7o has documented P2BAD on 2 Peugeot models: 3008, 308.