[SOLVED] P21C5 Code: How To Fix Stuck Reductant Level Sensor ‘a’

If you see the engine light on or the service engine soon warning light, it could be due to the P21C5 fault code.

This code indicates a problem with the Reductant Level Sensor ‘A’ or its circuit. The possible causes include a faulty sensor, an open or shorted harness, or a poor electrical connection.

It could also be due to a faulty Engine Control Module (ECM). The importance of repairing this issue lies in the fact that it affects the vehicle’s emissions system. The difficulty level of the repair is moderate, and it takes about 1.0 hour to fix.

To interpret the fault code, you need to check the possible causes listed above and visually inspect the related wiring harness and connectors.

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 p21c5 fault code. Here are the symptoms to look out for:

  • The P21C5 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, stalling, and difficulty starting the engine.
  • Additionally, the vehicle may experience transmission shifting issues, 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.

The P21C5 automobile fault code can be caused by a faulty reductant level sensor, open or shorted harness, poor electrical connection, or a faulty ECM.

  • The automobile fault code P21C5 can be caused by a faulty Reductant Level Sensor ‘A’.
  • It can also be caused by an open or shorted harness of the Reductant Level Sensor ‘A’.
  • Poor electrical connection in the Reductant Level Sensor ‘A’ circuit can also trigger this fault code.
  • Lastly, a faulty Engine Control Module (ECM) can also be a cause of the P21C5 fault code.

To fix the automobile fault code p21c5, check the possible causes and inspect related components for damage or corrosion.

  • To fix the automobile fault code P21C5, first, check the possible causes listed above.
  • Then, visually inspect the related wiring harness and connectors.
  • Look for any 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 P21C5 indicates an issue with the engine coolant pump control circuit. The estimated repair time for this fault code is 1.0 hour.

The cost of fixing this issue can vary depending on the auto repair shop, but it is common for most shops to charge between $75 and $150 per hour.

Other factors that may influence the cost include the severity of the issue, the type of vehicle, and the location of the repair shop.

The P21C5 fault code indicates that the Reductant Level Sensor ‘A’ is stuck.

This sensor is a part of the Diesel Exhaust Fluid (DEF) system, which is responsible for reducing harmful Oxides of Nitrogen (NOx) emissions. The DEF system requires a storage tank, pump, pressure sensor, fluid quality sensor, injector, fluid heater, and catalyst. The Reductant Level Sensor ‘A’ is responsible for monitoring the level of DEF in the storage tank.

If this sensor is stuck, it can cause incorrect readings and affect the proper functioning of the DEF system.

It is important to address this fault code promptly to ensure the vehicle’s exhaust gas emissions remain within acceptable limits.

What are the possible causes of the P21C5 fault code in an automobile?

If you’re experiencing the P21C5 fault code in your automobile, you may notice that the engine light is on. This could be due to a faulty Reductant Level Sensor ‘A’, an open or shorted harness, poor electrical connection in the circuit, or a faulty Engine Control Module (ECM). To fix the issue, it’s important to 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 wiring harness and connectors related to the Reductant Level Sensor ‘A’?

If the engine light is on due to a faulty Reductant Level Sensor ‘A’, it is important to visually inspect the related wiring harness and connectors. Check for any damaged components and look for broken, bent, pushed out, or corroded connector’s pins. This could be the result of an open or shorted harness, poor electrical connection, or a faulty Engine Control Module (ECM). To fix the issue, check the possible causes listed above and take necessary actions.

What are the consequences of ignoring the P21C5 fault code in an automobile?

Ignoring the P21C5 fault code in an automobile, which is indicated by the engine light being on, can lead to serious consequences. The fault is caused by a faulty reductant level sensor ‘A’, an open or shorted harness, poor electrical connection, or a faulty engine control module. To fix the issue, one must visually inspect the wiring harness and connectors, check for damaged components, and look for broken, bent, pushed out, or corroded connector’s pins. Failure to address the issue can lead to reduced engine performance, increased emissions, and potential damage to the engine.

p21c5 error fault code explained

If your engine light is on and the fault code is P21C5, it may be due to a faulty Reductant Level Sensor ‘A’, an open or shorted harness, poor electrical connection, or a faulty Engine Control Module (ECM). Visually inspect the wiring harness and connectors for damage and check for broken, bent, pushed out, or corroded connector pins.

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