P0038 2018 GMC Sierra Code - HO2S Heater Control Circuit High Voltage Bank 1 Sensor 2
Quick Answer
The P0038 diagnostic trouble code (DTC) for a 2018 GMC Sierra refers to an issue with the HO2S (Heated Oxygen Sensor) heater control circuit on Bank 1 Sensor 2. Common causes include Faulty Oxygen Sensor: The most common cause of the P0038 code is a malfunctioning HO2S heater control circuit on Bank 1 Sensor 2, Wiring Issues: Damaged or corroded wiring leading to the oxygen sensor can cause high voltage in the heater control circuit, Poor Electrical Connection: Loose or poor electrical connections to the oxygen sensor can also trigger the P0038 code. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
- What it means
- P0038 2018 GMC Sierra indicates HO2S Heater Control Circuit High Voltage Bank 1 Sensor 2.
- Common causes
- Common causes include Faulty Oxygen Sensor: The most common cause of the P0038 code is a malfunctioning HO2S heater control circuit on Bank 1 Sensor 2, Wiring Issues: Damaged or corroded wiring leading to the oxygen sensor can cause high voltage in the heater control circuit, Poor Electrical Connection: Loose or poor electrical connections to the oxygen sensor can also trigger the P0038 code.
- Severity
- Moderate - service should be scheduled soon.
- Can I drive?
- The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
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 P0038 2018 GMC Sierra Description
The P0038 diagnostic trouble code (DTC) for a 2018 GMC Sierra refers to an issue with the HO2S (Heated Oxygen Sensor) heater control circuit on Bank 1 Sensor 2. The HO2S is a critical component of the vehicle's emission control system, responsible for monitoring the oxygen content in the exhaust gases to help the engine control module (ECM) adjust the air-fuel mixture for optimal combustion efficiency. Bank 1 refers to the side of the engine where the number 1 cylinder is located, while Sensor 2 indicates that it is the downstream oxygen sensor in the exhaust system.
Common Causes of P0038 2018 GMC Sierra
- Faulty Oxygen Sensor: The most common cause of the P0038 code is a malfunctioning HO2S heater control circuit on Bank 1 Sensor 2.
- Wiring Issues: Damaged or corroded wiring leading to the oxygen sensor can cause high voltage in the heater control circuit.
- Poor Electrical Connection: Loose or poor electrical connections to the oxygen sensor can also trigger the P0038 code.
- ECM Malfunction: A malfunctioning engine control module (ECM) can incorrectly interpret sensor data, leading to the P0038 code.
- Exhaust System Leaks: Exhaust leaks near the oxygen sensor can cause the heater control circuit to draw excessive voltage.
Symptoms of P0038 2018 GMC Sierra
- Check Engine Light: The most common symptom associated with the P0038 code is the illumination of the check engine light on the vehicle's dashboard.
- Reduced Fuel Efficiency: A malfunctioning HO2S can lead to incorrect fuel mixture adjustments, resulting in decreased fuel efficiency.
- Rough Idle: An imbalance in the air-fuel mixture can cause the engine to idle roughly or inconsistently.
- Engine Misfires: Incorrect oxygen readings can also lead to engine misfires, causing the vehicle to run unevenly or shake.
- Failed Emissions Test: A faulty oxygen sensor can cause the vehicle to fail emissions tests due to increased pollutant emissions.
How to Fix P0038 2018 GMC Sierra
- Diagnose the Issue: Use an OBD-II scanner to retrieve the P0038 code and then perform a visual inspection of the oxygen sensor and its wiring.
- Test the Oxygen Sensor: Check the resistance of the oxygen sensor's heating element to determine if it is functioning correctly.
- Inspect Wiring and Connections: Thoroughly inspect the wiring leading to the oxygen sensor for any damage or corrosion, and ensure secure electrical connections.
- Replace Oxygen Sensor: If the oxygen sensor's heating element is faulty or damaged, replace the sensor with a new, OEM-quality part.
- Clear the Code: After the repair is completed, clear the P0038 code from the ECM's memory using the OBD-II scanner to reset the check engine light.
Cost to Fix P0038 2018 GMC Sierra
The typical repair costs for addressing the P0038 code on a 2018 GMC Sierra can vary depending on factors such as the location of the repair shop, the make and model of the vehicle, and the labor rates in the area. On average, the cost of replacing an oxygen sensor can range from $200 to $400, including parts and labor. However, additional costs may apply if wiring repairs or ECM diagnostics are necessary. It is advisable to obtain quotes from local auto repair shops to get a more accurate estimate of the repair costs for this issue. Remember that labor rates can range from $80 to $150 per hour, with rates potentially higher at dealerships or in metropolitan areas.
Tech Notes for P0038 2018 GMC Sierra
Need more information about the P0038 2018 GMC Sierra code?
Need more information on how to fix the P0038 2018 GMC Sierra code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P0038 2018 GMC Sierra code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about P0038 2018 GMC Sierra Code
No Frequently Asked Questions about P0038 2018 GMC Sierra Code found.
Discuss the causes and fixes for P0038 2018 GMC Sierra OBDII Code
Code P0038 2018 GMC Sierra 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.