P20C8 Code - Reductant Heater 'D' Control Circuit High
Quick Answer
The P20C8 diagnostic trouble code indicates an issue with the Reductant Heater 'D' Control Circuit being detected as high. Common causes include Faulty Reductant Heater: The heater itself may be malfunctioning, causing the circuit to report high voltage, Wiring Issues: Corrosion, damage, or poor connections in the wiring harness can disrupt the flow of electricity to the heater, Heater Control Module Failure: A malfunctioning control module can result in improper voltage regulation in the circuit. 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
- P20C8 indicates Reductant Heater 'D' Control Circuit High.
- Common causes
- Common causes include Faulty Reductant Heater: The heater itself may be malfunctioning, causing the circuit to report high voltage, Wiring Issues: Corrosion, damage, or poor connections in the wiring harness can disrupt the flow of electricity to the heater, Heater Control Module Failure: A malfunctioning control module can result in improper voltage regulation in the circuit.
- 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.
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Code P20C8 Description
The P20C8 diagnostic trouble code indicates an issue with the Reductant Heater 'D' Control Circuit being detected as high. This code is commonly found in vehicles equipped with a diesel engine and a Selective Catalytic Reduction (SCR) system. The Reductant Heater is responsible for heating the diesel exhaust fluid (DEF) to a certain temperature before it is injected into the SCR system to reduce harmful emissions.
Common Causes of P20C8
- Faulty Reductant Heater: The heater itself may be malfunctioning, causing the circuit to report high voltage.
- Wiring Issues: Corrosion, damage, or poor connections in the wiring harness can disrupt the flow of electricity to the heater.
- Heater Control Module Failure: A malfunctioning control module can result in improper voltage regulation in the circuit.
- Power Supply Problem: Issues with the power supply to the Reductant Heater can cause the circuit to report high voltage.
Symptoms of P20C8
- Check Engine Light: The most common symptom associated with this code 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 engine running in a safe mode to protect itself from further damage.
- Poor Fuel Economy: A malfunctioning Reductant Heater can lead to poor fuel efficiency as the SCR system may not be operating at optimal levels.
- Increased Emissions: The vehicle may fail emissions tests or emit higher levels of harmful gases due to the inefficient operation of the SCR system.
How to Fix P20C8
- Diagnose the Issue: Use a diagnostic scanner to retrieve the specific code and pinpoint the exact cause of the problem.
- Inspect Wiring: Check the wiring harness for any signs of damage, corrosion, or loose connections. Repair or replace as necessary.
- Test Reductant Heater: Test the Reductant Heater for proper function and replace if found to be faulty.
- Check Control Module: Inspect the control module for any issues and replace if needed.
- Clear Codes: After completing the repairs, clear the diagnostic trouble codes and test drive the vehicle to ensure the issue has been resolved.
Cost to Fix P20C8
The cost of repairing a Reductant Heater 'D' Control Circuit High issue can vary depending on the extent of the problem and the specific components that need to be replaced. On average, the parts for this repair can range from $200 to $500, while labor costs may add an additional $100 to $200. It's important to note that labor rates at auto repair shops can vary, so it's recommended to obtain quotes from multiple shops in your area to get a more accurate estimate.
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Code P20C8 Information for Specific Makes
- P20C8 Chevrolet — Reductant Heater 'D' Control Circuit High
- P20C8 Ford — Reductant Heater 'D' Control Circuit High
- P20C8 GMC — Reductant Heater 'D' Control Circuit High
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