The P21CB fault code in automobiles indicates a problem with the Reductant Control Module, which can cause the engine light to turn on.

This fault code can be caused by a faulty module, an open or shorted harness, or poor electrical connections. It is important to address this issue promptly as it can lead to reduced engine performance and increased emissions. The repair process involves visually inspecting the wiring harness and connectors for any damage or corrosion.

The repair time for this fault code is estimated to be around 1.0 hour. To interpret the fault code, it is recommended to check the possible causes listed above and visually inspect the related components.

Repair Importance Level10.0 (Out of 10)
Estimated Repair TimeApproximately 1.0 hour
Repair Difficulty Level10.0 (Out of 10)

If you notice the Engine Light ON or Service Engine Soon Warning Light, it could be a sign of p21cb fault code.

Here are the symptoms to look out for:

  • The P21CB fault code in an automobile can cause several symptoms, including the engine light turning on or the service engine soon warning light appearing.
  • Other symptoms may include reduced engine power, decreased fuel efficiency, rough idling, and difficulty starting the engine.
  • Additionally, the vehicle may experience stalling or hesitation during acceleration, and there may be a noticeable decrease in overall performance.
  • It is important to address these symptoms promptly to prevent further damage to the vehicle and ensure safe operation on the road.

P21CB fault code can be caused by a faulty reductant control module, open or shorted harness, or poor electrical connection.

  • The automobile fault code P21CB can be caused by a faulty Reductant Control Module.
  • It can also be caused by an open or shorted Reductant Control Module harness.
  • Additionally, a poor electrical connection in the Reductant Control Module circuit can also trigger this fault code.

To fix the automobile fault code p21cb, check the possible causes and inspect the related wiring harness and connectors for any damage or corrosion.

  • To fix the automobile fault code P21CB, you need to check the possible causes listed above.
  • Inspect the wiring harness and connectors visually.
  • Look for damaged components and check for broken, bent, pushed out, or corroded connector’s pins.
  • This fix will take an estimated repair time of 1.0 hour.

The fault code P21CB indicates an issue with the NOx sensor circuit. The diagnosis involves checking the wiring and connections of the sensor.

The fixing cost depends on the repair time, which is estimated to be 1.0 hour. Most auto repair shops charge between $75 and $150 per hour, which will affect the total cost. It is important to address this issue promptly to avoid further damage to the vehicle and ensure it is running efficiently.

The P21CB fault code is related to the selective catalytic reduction system in automobiles. This system reduces Oxides of Nitrogen (NOx) emissions by injecting a metered amount of reductant into the exhaust gas stream.

The Engine Control Module (ECM) and the Reductant Control Module work together to control the reductant injector duty cycle in response to changes in engine-out NOx levels. The P21CB code is set when the Reductant Control Module supply voltage is less than a calibrated value for greater than 5 s.

What are the possible causes of the P21CB automobile fault code?

If you see the engine light on or the service engine soon warning light, it could be due to the P21CB fault code. This code is caused by a faulty Reductant Control Module, an open or shorted harness, or poor electrical connection in the module circuit. To fix this issue, you should visually inspect the wiring harness and connectors, check for damaged components, and look for broken, bent, pushed out, or corroded connector’s pins.

How can one visually inspect the related wiring harness and connectors to fix the P21CB fault code?

If you’re experiencing the P21CB fault code, which is indicated by the Engine Light ON or Service Engine Soon Warning Light, you may need to visually inspect the related wiring harness and connectors to fix the issue. This fault code can be caused by a faulty Reductant Control Module, an open or shorted Reductant Control Module harness, or a poor electrical connection in the Reductant Control Module circuit. To fix the issue, check the possible causes listed above and visually inspect the wiring harness and connectors for any damage or corrosion. Look for broken, bent, pushed out, or corroded connector pins.

What are the signs of damaged components that one should look for when fixing the P21CB fault code?

If you’re dealing with a P21CB fault code, you should look out for the engine light being on or the service engine soon warning light. The possible causes of this issue include a faulty reductant control module, an open or shorted reductant control module harness, or a poor electrical connection in the reductant control module circuit. To fix this problem, you should visually inspect the related wiring harness and connectors, check for damaged components, and look for broken, bent, pushed out, or corroded connector’s pins.

p21cb error fault code explained

If you see the Engine Light ON or Service Engine Soon Warning Light, it could be due to a faulty Reductant Control Module, open or shorted harness, or poor electrical connection. Check the possible causes, inspect the wiring harness and connectors, and look for damaged components or corroded pins.

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