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NOx sensor failure

NOx gases are absorbed and collected in the NOx converter.

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Costs

Every car issue can be caused by different things. Here are the most common ones

Most Expensive

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Potential Causes

  • Spare parts
  • Work time
Moderate costs

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Potential Causes

  • Spare parts
  • Work time
Cheapest case

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Potential Causes

  • Spare parts
  • Work time

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Discussions

User of our Carly Community asked the following questions regarding that fault:

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Details

Probability

Based on the values and symptoms you have entered, a crude estimation of the probability of this problem can be made

high-probability

HIGH

Typical consequences

If this defect is detected, it may lead to the following problems:

  • Exhaust system damage
  • Failure of the exhaust emission test (Failure to pass the exhaust emission test)

Function of NOx sensor

The nitrogen oxide sensor (also called NOx sensor) consists of a measuring probe and an associated control unit. The two parts cannot be separated. The control unit of the nitrogen oxide sensor communicates with the engine control unit via the local CAN.

The nitrogen oxide sensor functions in a similar way to a lambda sensor. The measuring method is based on a measurement of the oxygen content, which enables a conclusion to be drawn about the nitrogen oxide content. In addition, the NOx sensor has a heater. It is activated as soon as the vehicle is started. The heater is active until the NOx sensor is in the optimum operating state.

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