P20C0 GMC Code - Reductant Heater 2 Control Circuit High Voltage
Quick Answer
The P20C0 diagnostic trouble code for GMC vehicles specifically relates to an issue with the Reductant Heater 2 Control Circuit registering high voltage. Common causes include Faulty Reductant Heater: A malfunctioning Reductant Heater itself can cause high voltage in the circuit, triggering the P20C0 code, Wiring Issues: Damaged or corroded wiring in the Reductant Heater 2 Control Circuit can disrupt the flow of voltage and lead to high readings, ECM Malfunction: A problem with the engine control module (ECM) responsible for monitoring the Reductant Heater 2 Control Circuit can also trigger this code. 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
- P20C0 GMC indicates Reductant Heater 2 Control Circuit High Voltage.
- Common causes
- Common causes include Faulty Reductant Heater: A malfunctioning Reductant Heater itself can cause high voltage in the circuit, triggering the P20C0 code, Wiring Issues: Damaged or corroded wiring in the Reductant Heater 2 Control Circuit can disrupt the flow of voltage and lead to high readings, ECM Malfunction: A problem with the engine control module (ECM) responsible for monitoring the Reductant Heater 2 Control Circuit can also trigger this code.
- 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 P20C0 GMC Description
The P20C0 diagnostic trouble code for GMC vehicles specifically relates to an issue with the Reductant Heater 2 Control Circuit registering high voltage. In vehicles equipped with a Selective Catalytic Reduction (SCR) system, the Reductant Heater is responsible for heating the Diesel Exhaust Fluid (DEF) before it is injected into the exhaust stream to reduce harmful emissions. When the engine control module (ECM) detects that the voltage in the Reductant Heater 2 Control Circuit is above the specified range, it triggers the P20C0 code.
Common Causes of P20C0 GMC
- Faulty Reductant Heater: A malfunctioning Reductant Heater itself can cause high voltage in the circuit, triggering the P20C0 code.
- Wiring Issues: Damaged or corroded wiring in the Reductant Heater 2 Control Circuit can disrupt the flow of voltage and lead to high readings.
- ECM Malfunction: A problem with the engine control module (ECM) responsible for monitoring the Reductant Heater 2 Control Circuit can also trigger this code.
- Sensor Malfunction: A faulty sensor that is providing incorrect voltage readings to the ECM can cause the circuit to register high voltage.
Symptoms of P20C0 GMC
- Check Engine Light: The most common symptom associated with the P20C0 code is the illumination of the Check Engine Light on the vehicle's dashboard.
- Reduced Engine Performance: The vehicle may experience a decrease in engine performance, including reduced power and acceleration.
- Poor Fuel Efficiency: High voltage in the Reductant Heater 2 Control Circuit can lead to poor fuel efficiency as the engine may not be operating at optimal levels.
- Emissions Issues: The vehicle may fail emissions tests due to the ineffective operation of the SCR system.
How to Fix P20C0 GMC
- Diagnose the Issue: Begin by using a diagnostic scanner to retrieve the specific trouble code and pinpoint the exact cause of the high voltage in the Reductant Heater 2 Control Circuit.
- Inspect Wiring: Check the wiring harness for any damage, corrosion, or loose connections. Repair or replace any faulty wiring as needed.
- Test Reductant Heater: Test the Reductant Heater itself to ensure it is functioning properly. Replace the heater if it is found to be faulty.
- Check Sensors: Test the sensors related to the Reductant Heater 2 Control Circuit to determine if any are providing incorrect readings. Replace any faulty sensors.
- Clear Codes: After completing the repairs, clear the diagnostic trouble codes from the ECM and test drive the vehicle to ensure the issue has been resolved.
Cost to Fix P20C0 GMC
The cost of repairing the P20C0 code for a GMC vehicle can vary depending on the specific cause of the issue and the extent of the repairs needed. In general, the cost of parts for replacing a faulty Reductant Heater or sensors can range from $200 to $500. Labor costs at auto repair shops typically range from $80 to $150 per hour, with the total repair cost likely falling between $300 and $800. It's important to note that additional diagnostic time may be required to accurately diagnose the issue, and labor rates can vary based on location and the specific repair shop. It's recommended to obtain a detailed quote from a trusted auto repair professional before proceeding with the repairs.
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Information for Specific GMC Models
- P20C0 2014 GMC Sierra — Reductant Heater 2 Control Circuit High Voltage
- P20C0 2015 GMC Sierra — Reductant Heater 2 Control Circuit High Voltage
- P20C0 2016 GMC Sierra — Reductant Heater 2 Control Circuit High Voltage
- P20C0 2017 GMC Sierra — Reductant Heater 2 Control Circuit High Voltage
- P20C0 2018 GMC Sierra — Reductant Heater 2 Control Circuit High Voltage
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