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Showing matches for "NOx sensor".
P2201: NOx sensor circuit range / performance
A NOx sensor signal or its controller behavior is outside the expected operating range.
AdBlue and NOx Faults: What Modern Diesel Buyers Should Know
A practical technical guide to SCR systems, NOx sensors, AdBlue pumps, countdown warnings, and why diesel emissions faults can become expensive.
P20EE: SCR NOx catalyst efficiency below threshold
The SCR system is not reducing NOx emissions as effectively as the ECU expects.
P2BA9: NOx exceedance due to insufficient reductant quality
The SCR system calculates excessive NOx emissions associated with reductant quality or dosing performance.
P0030: Heated oxygen sensor heater control circuit, bank 1 sensor 1
The ECU detects an electrical fault in the heater circuit for the upstream oxygen sensor.
P0130: Oxygen sensor circuit malfunction, bank 1 sensor 1
The upstream oxygen or lambda sensor signal is implausible, missing, or outside the control range expected by the ECU.
P0135: Oxygen sensor heater circuit, bank 1 sensor 1
The upstream oxygen sensor heater circuit is not operating as expected.
P0141: Oxygen sensor heater circuit, bank 1 sensor 2
The downstream oxygen sensor heater circuit is not reaching expected operation.
P0325: Knock sensor circuit malfunction
The ECU is not receiving a plausible signal from the knock sensor circuit.
P0471: Exhaust pressure sensor range / performance
The exhaust-pressure sensor signal is implausible for engine load, speed, and DPF pressure conditions.
P0544: Exhaust-gas temperature sensor circuit, bank 1 sensor 1
The ECU sees an electrical fault in an exhaust-temperature sensor used to protect the turbo and emissions system.
P0641: Sensor reference voltage A circuit open
A shared 5-volt reference circuit for engine sensors is missing, shorted, or pulled out of range.
P2195: Oxygen sensor signal stuck lean, bank 1 sensor 1
The upstream oxygen sensor on bank 1 remains at a lean indication despite ECU correction.
P0113: Intake-air temperature sensor circuit high
The ECU sees an intake-air temperature signal that is higher voltage than expected, often interpreted as an unrealistically cold reading.
P0118: Engine coolant temperature sensor circuit high
The coolant-temperature signal is implausibly high voltage, often read by the ECU as extremely cold coolant.
P0121: Throttle / pedal position sensor range / performance
The ECU sees a throttle or accelerator-position signal that is outside the expected relationship.
P0191: Fuel rail pressure sensor range / performance
The rail-pressure signal is implausible or does not follow commanded pressure correctly.
P0236: Turbo boost sensor range / performance
The charge-pressure signal is outside the expected range or disagrees with operating conditions.
P0335: Crankshaft position sensor circuit
The ECU is missing or cannot trust the crankshaft position signal.
P0340: Camshaft position sensor circuit, bank 1
The ECU is missing or cannot trust the camshaft position signal on bank 1.
P0706: Transmission range sensor circuit range / performance
The selected gear or park/neutral signal is implausible for the transmission's actual state.
P0715: Input / turbine speed sensor circuit
The transmission controller cannot trust the input or turbine speed signal.
P2135: Throttle position sensor correlation
The redundant throttle-position signals disagree beyond the permitted tolerance.
P2453: DPF differential-pressure sensor range / performance
The pressure signal used to calculate DPF restriction is implausible or outside range.
P2563: Turbocharger boost-control position sensor range / performance
The reported turbo actuator position does not match the requested or mechanically possible range.
P204F: Reductant system performance
The reductant system is not meeting the performance expected by the emissions controller.
P0101: Mass-air-flow signal range / performance
Airflow reported by the MAF sensor does not agree with the ECU's calculated operating conditions.
P0102: Mass-air-flow circuit low input
The MAF sensor signal is lower than expected for the engine speed and load.
P0106: Manifold absolute pressure range / performance
The MAP sensor signal does not match the pressure expected from throttle position, boost, engine speed, and airflow.
P0420: Catalyst efficiency below threshold, bank 1
Upstream and downstream oxygen-sensor behavior suggests insufficient catalyst oxygen-storage performance.
P0017: Crankshaft / camshaft timing correlation, bank 1 sensor B
The exhaust-camshaft and crankshaft signals on bank 1 are outside their expected relationship.
2019 Mercedes-Benz C-Class Reliability and Buying Guide
A focused guide to 2019 W205 C-Class reliability, 9G-Tronic behavior, diesel emissions, electronics, and used-car checks.
2019 Volkswagen Golf Reliability and Buying Guide
A buyer-focused view of the 2019 Golf Mk7.5, covering TSI/TDI engines, DSG servicing, cooling, electronics, and inspection.
BMW B47
A more mature BMW four-cylinder diesel with improved timing architecture but continued emissions and service sensitivity.
C1130: Chassis control or suspension pressure fault
A chassis or suspension control module has detected an implausible pressure, height, or control-state condition.
Mercedes-Benz Brand Hub
Mercedes-Benz reliability analysis, common problems, buying guides, and engineering-driven ownership insights.