[SOLVED] P20C4 Code: Fixing High Control Circuit In Reductant Heater ‘c’

The P20C4 fault code in automobiles indicates a problem with the reductant heater system. The most common symptom is the illumination of the engine light or service engine soon warning light.

The cause of this issue could be a faulty reductant heater, an open or shorted reductant heater harness, or a poor electrical connection in the reductant heater circuit.

The importance of repairing this issue lies in the fact that it can lead to increased emissions and reduced fuel efficiency. The repair difficulty is moderate, with a repair time of 1.0. To fix the problem, one should visually inspect the wiring harness and connectors, check for damaged components, and look for broken, bent, pushed out, or corroded connector pins.

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 or service engine soon warning light on, it could be a sign of P20C4 fault code. Here are the symptoms to look out for:

  • The P20C4 fault code in an automobile can cause several symptoms.
  • The most common symptom is the illumination of the engine light or service engine soon warning light.
  • Other symptoms include reduced engine power, poor acceleration, rough idling, stalling, and decreased fuel efficiency.
  • Additionally, the vehicle may experience difficulty starting, 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 P20C4 automobile fault code can be caused by a faulty reductant heater, open or shorted harness, or poor electrical connection.

  • The automobile fault code P20C4 can be caused by a faulty reductant heater.
  • It can also be caused by an open or shorted reductant heater harness.
  • Additionally, a poor electrical connection in the reductant heater circuit can also trigger this fault code.

Below are the possible fixes for the automobile fault code p20c4, including inspecting wiring harness and connectors for damage.

  • To fix the automobile fault code P20C4, 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 P20C4 indicates an issue with the reductant heater 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 them 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 P20C4 fault code indicates a problem with the Reductant Heater ‘C’ Control Circuit.

The Reductant Heater and Sender Assembly contains a heating element that thaws liquid reductant during cold temperatures.

When the PCM detects the temperature dropping to freezing point, it commands the glow plug control module to provide voltage to the heating element. If the control circuit is high, it means that there is an issue with the heating element or the circuit that controls it.

What are the possible causes of the P20C4 automobile fault code?

If you see the engine light on or the service engine soon warning light, it could be due to the P20C4 fault code. This code is caused by a faulty reductant heater, an open or shorted reductant heater harness, or a poor electrical connection in the reductant heater 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 I visually inspect the wiring harness and connectors related to the Reductant Heater?

If you’re experiencing an Engine Light ON or Service Engine Soon Warning Light, it could be due to a faulty Reductant Heater or a poor electrical connection in the Reductant Heater circuit. To fix this issue, you should 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 will help you identify any open or shorted circuits and ensure that the Reductant Heater is functioning properly.

What are the consequences of not fixing the P20C4 automobile fault code?

Ignoring the P20C4 fault code in your automobile can lead to serious consequences. The engine light will remain on, indicating a problem with the reductant heater. This can cause the vehicle to fail emissions tests and reduce fuel efficiency. The root cause of the issue could be a faulty reductant heater, an open or shorted harness, or poor electrical connections. It is important to visually inspect the wiring harness and connectors and check for damaged components to avoid further damage.

p20c4 error fault code explained

If your engine light is on, it could be due to a faulty reductant heater, an open or shorted harness, or poor electrical connection. Visually inspect the wiring harness and connectors for damage or corrosion.

Check for broken, bent, or pushed out pins.

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