U059F: Ungültige Daten vom NOx-Sensor B empfangen
Was zu tun ist
This concerns your car's emissions monitoring, and it is one to deal with rather than defer — because the law obliges the car to escalate.
On a modern diesel, if the system cannot verify its emissions performance, the vehicle will warn you and then start reducing power, and on some vehicles eventually refuse to restart after fuelling. That escalation stops only when the fault is fixed — there is no reset that argues with it.
Ask specifically for the wiring and connector to be inspected before the sensor is replaced. NOx sensors are expensive, they live in the exhaust where salt and heat destroy wiring, and a damaged harness looks exactly like a failed sensor while costing a fraction to repair.
If most of your journeys are short, mention it. A diesel that never gets fully warm ages these sensors and the aftertreatment early, and a longer run at speed occasionally genuinely helps.
Was dieser Code bedeutet
NOx sensor B is broadcasting data that cannot be accepted as true. See U0400 for what an invalid-data code is and why the module it names is usually the messenger rather than the culprit.
The letter narrows the fault to one instance of a repeated module, and that is genuinely useful — but it does not say which one physically. The mapping from letter to position is the manufacturer's choice and differs between makes, so only the vehicle's own documentation resolves it.
Two consequences. Several letters stored together means the fault is upstream of all of them — a shared supply, a shared earth, or the bus. Exactly one letter stored is the more informative case: the others are working, so everything they share is proven good.
A NOx sensor measures oxides of nitrogen in the exhaust, and on a modern diesel it is the instrument the whole emissions strategy is judged by.
Two of them is the normal arrangement: one upstream of the aftertreatment and one downstream, so the vehicle can measure how much NOx the system is actually removing. The comparison between them is the efficiency figure the law cares about.
Which is why an invalid reading has consequences beyond a warning light. The vehicle cannot demonstrate its emissions performance without it, and diesel emissions regulation obliges the vehicle to respond — warnings first, then torque reduction, and on some vehicles a restricted restart. The corpus documents that inducement ladder at P2BAF.
These sensors live in the exhaust and fail from where they live. Thermal cycling, road salt on the wiring, and vibration crack the harness; the sensing element itself is poisoned slowly by contaminated fuel or oil consumption, and by repeated short journeys that never bring the aftertreatment to temperature.
One diagnostic that costs nothing: NOx sensors are expensive, and a wiring fault presents identically. Inspect the harness and connector before condemning the sensor, because that is where the fault usually is and the difference in price is substantial.
Wahrscheinliche Ursachen
Hier anfangen
- NOx-Sensor defekt · Fachwerkstatt
- Korrodierter oder loser Stecker · mittel
- Kabelbaum beschädigt · mittel
Seltener
- Hitzeschaden an Sensor oder Leitung · mittel
- Datenbusleitungen beschädigt · mittel
Symptome
Beteiligte Bauteile
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