P20C3 Code - Reductant Heater 'C' Control Circuit Low
Quick Answer
The P20C3 diagnostic trouble code (DTC) indicates a problem with the Reductant Heater 'C' Control Circuit being detected as low by the vehicle's onboard computer system. Common causes include Faulty Reductant Heater: The reductant heater itself may be malfunctioning, causing the control circuit to register a low voltage, Wiring Issues: Damage or corrosion in the wiring connecting the reductant heater to the vehicle's electrical system can cause a low voltage reading, Defective Control Module: A faulty SCR control module can also trigger the P20C3 code by not sending the correct signals to the reductant heater. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P20C3 indicates Reductant Heater 'C' Control Circuit Low.
- Common causes
- Common causes include Faulty Reductant Heater: The reductant heater itself may be malfunctioning, causing the control circuit to register a low voltage, Wiring Issues: Damage or corrosion in the wiring connecting the reductant heater to the vehicle's electrical system can cause a low voltage reading, Defective Control Module: A faulty SCR control module can also trigger the P20C3 code by not sending the correct signals to the reductant heater.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
Code P20C3 Description
The P20C3 diagnostic trouble code (DTC) indicates a problem with the Reductant Heater 'C' Control Circuit being detected as low by the vehicle's onboard computer system. The reductant heater is a component of the Selective Catalytic Reduction (SCR) system, which is responsible for reducing harmful emissions in diesel vehicles. The reductant heater warms up the Diesel Exhaust Fluid (DEF) to prevent it from freezing in cold temperatures, allowing it to effectively react with the exhaust gases to reduce nitrogen oxide emissions.
Common Causes of P20C3
- Faulty Reductant Heater: The reductant heater itself may be malfunctioning, causing the control circuit to register a low voltage.
- Wiring Issues: Damage or corrosion in the wiring connecting the reductant heater to the vehicle's electrical system can cause a low voltage reading.
- Defective Control Module: A faulty SCR control module can also trigger the P20C3 code by not sending the correct signals to the reductant heater.
- Poor Electrical Connection: Loose or poor electrical connections can disrupt the flow of voltage to the reductant heater, leading to a low voltage reading.
Symptoms of P20C3
- Check Engine Light: The most common symptom associated with this DTC is the illumination of the check engine light on the vehicle's dashboard.
- Reduced Power: The vehicle may experience a loss of power or reduced performance due to the reductant heater not functioning properly.
- Increased Emissions: The vehicle may emit higher levels of harmful emissions due to the inefficient operation of the SCR system.
- Poor Fuel Efficiency: A malfunctioning reductant heater can lead to decreased fuel efficiency as the SCR system may not be operating optimally.
How to Fix P20C3
- Diagnose the Issue: Use a diagnostic scanner to retrieve the DTC and pinpoint the exact cause of the problem.
- Inspect Wiring and Connections: Check the wiring harness and connections to ensure they are intact and free of damage or corrosion.
- Test Reductant Heater: Test the reductant heater to determine if it is functioning properly and replace it if necessary.
- Check Control Module: Inspect the SCR control module for any faults or defects and replace it if needed.
- Clear DTC and Test Drive: Clear the DTC from the vehicle's computer system, conduct a test drive to ensure the issue is resolved, and verify that the check engine light does not reappear.
Cost to Fix P20C3
The typical repair costs for addressing a P20C3 DTC can vary depending on the specific cause of the issue. In general, replacing a faulty reductant heater can cost between $200 and $500, including parts and labor. However, if the problem lies with the wiring or control module, the repair costs may increase. It's important to consider the diagnosis time and labor rates at auto repair shops, which can range from $80 to $150 per hour. Additionally, rates may vary based on the vehicle's make and model, engine type, and location. For a more accurate cost estimate, it's recommended to consult with a local auto repair shop.
Need more information about the P20C3 code?
Need more information on how to fix the P20C3 code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P20C3 code diagnosed by a professional: Find a repair shop in your area
Code P20C3 Information for Specific Makes
- P20C3 Chevrolet — Reductant Heater 'C' Control Circuit Low
- P20C3 Ford — Reductant Heater 'C' Control Circuit Low
- P20C3 GMC — Reductant Heater 'C' Control Circuit Low
Frequently Asked Questions about P20C3 Code
1. What are the common symptoms of OBDII code P20C3 related to the Reductant Heater 'C' Control Circuit Low?
- Common symptoms include the check engine light being illuminated, reduced engine performance, and potential issues with emissions control.
2. What could be causing the Reductant Heater 'C' Control Circuit Low fault code P20C3?
- Possible causes may include a faulty reductant heater, damaged wiring or connectors in the heater circuit, or issues with the powertrain control module (PCM).
3. How can I diagnose the cause of OBDII code P20C3 indicating a Reductant Heater 'C' Control Circuit Low?
- Diagnosis typically involves checking the reductant heater for proper operation, inspecting the wiring and connectors for damage, and using a diagnostic scan tool to assess the PCM's communication with the heater circuit.
4. Can I continue driving my vehicle with OBDII code P20C3 present?
- It is not recommended to ignore this fault code, as it can lead to decreased fuel efficiency, increased emissions, and potential damage to the emissions control system. It is advisable to address the issue promptly.
5. What are the repair options for resolving OBDII code P20C3 indicating a Reductant Heater 'C' Control Circuit Low?
- Repair options may include replacing the faulty reductant heater, repairing any damaged wiring or connectors in the heater circuit, and resetting the fault code with a diagnostic tool after addressing the underlying issue.
6. Are there any DIY tips for troubleshooting OBDII code P20C3 at home?
- While basic checks like inspecting the wiring connections and ensuring the reductant heater is receiving power can be done at home, diagnosing and repairing the specific cause of the fault code may require professional equipment and expertise.
7. Will resetting the fault code clear OBDII code P20C3 related to the Reductant Heater 'C' Control Circuit Low?
- Resetting the fault code may temporarily turn off the check engine light, but if the underlying issue causing the fault code is not addressed, the code is likely to reappear upon further driving.
8. How urgent is it to address OBDII code P20C3 associated with the Reductant Heater 'C' Control Circuit Low?
- While your vehicle may still be operable with this fault code present, it is important to address it in a timely manner to prevent potential damage to the emissions control system and ensure optimal engine performance.
9. Can extreme weather conditions affect the likelihood of triggering OBDII code P20C3 for the Reductant Heater 'C' Control Circuit Low?
- Yes, extreme cold temperatures can sometimes lead to issues with reductant heaters, potentially increasing the likelihood of triggering this fault code. It is important to consider environmental factors when diagnosing the problem.
10. Is it necessary to visit a dealership or can an independent mechanic address OBDII code P20C3 related to the Reductant Heater 'C' Control Circuit Low?
- An independent mechanic with experience in diagnosing and repairing emissions control systems should be able to address this fault code effectively. Dealerships are also equipped to handle such issues, but independent mechanics may offer more cost-effective solutions.
Discuss the causes and fixes for P20C3 OBDII Code
Code P20C3 comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.