Engine-CodesGMC – P0158 2018 GMC Sierra

P0158 2018 GMC Sierra Code - HO2S Circuit High Voltage Bank 2 Sensor 2

Quick Answer

The P0158 diagnostic trouble code (DTC) indicates a high voltage condition in the heated oxygen sensor (HO2S) circuit for Bank 2, Sensor 2 of a 2018 GMC Sierra. Common causes include Faulty Oxygen Sensor: The most common cause is a malfunctioning Bank 2, Sensor 2 oxygen sensor that may be sending incorrect voltage signals, Wiring Issues: Damaged, frayed, or corroded wiring or connectors in the HO2S circuit can lead to high voltage readings, Short Circuit: A short circuit in the wiring harness can cause excessive voltage to be sent to the sensor. 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
P0158 2018 GMC Sierra indicates HO2S Circuit High Voltage Bank 2 Sensor 2.
Common causes
Common causes include Faulty Oxygen Sensor: The most common cause is a malfunctioning Bank 2, Sensor 2 oxygen sensor that may be sending incorrect voltage signals, Wiring Issues: Damaged, frayed, or corroded wiring or connectors in the HO2S circuit can lead to high voltage readings, Short Circuit: A short circuit in the wiring harness can cause excessive voltage to be sent to the sensor.
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.
Table of contents Created and updated by William Orellana on Oct 03, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P0158 2018 GMC Sierra Description

The P0158 diagnostic trouble code (DTC) indicates a high voltage condition in the heated oxygen sensor (HO2S) circuit for Bank 2, Sensor 2 of a 2018 GMC Sierra. The oxygen sensors are critical components in the vehicle's emissions control system, responsible for monitoring the oxygen levels in the exhaust gases. This information is relayed to the Engine Control Module (ECM), which adjusts the air-fuel mixture for optimal combustion efficiency.

OBDII Code P0158 2018 GMC Sierra - HO2S Circuit High Voltage Bank 2 Sensor 2
P0158 2018 GMC Sierra Code - HO2S Circuit High Voltage Bank 2 Sensor 2

Common Causes of P0158 2018 GMC Sierra

  1. Faulty Oxygen Sensor: The most common cause is a malfunctioning Bank 2, Sensor 2 oxygen sensor that may be sending incorrect voltage signals.
  2. Wiring Issues: Damaged, frayed, or corroded wiring or connectors in the HO2S circuit can lead to high voltage readings.
  3. Short Circuit: A short circuit in the wiring harness can cause excessive voltage to be sent to the sensor.
  4. Exhaust Leaks: Leaks in the exhaust system can lead to incorrect readings from the oxygen sensor, potentially causing high voltage conditions.
  5. ECM Malfunction: Although less common, a faulty Engine Control Module can misinterpret sensor data and trigger erroneous codes.

Symptoms of P0158 2018 GMC Sierra

  1. Check Engine Light: The most immediate symptom is the illumination of the check engine light on the dashboard.
  2. Poor Fuel Economy: Drivers may notice a significant decrease in fuel efficiency due to improper air-fuel mixture adjustments.
  3. Rough Idling: The vehicle may experience rough idling or stalling, particularly during cold starts.
  4. Increased Emissions: The vehicle may fail emissions tests due to improper readings from the oxygen sensor.
  5. Loss of Power: Drivers may experience a noticeable decrease in engine power and responsiveness, particularly during acceleration.

How to Fix P0158 2018 GMC Sierra

  1. Diagnostic Testing: Begin with a thorough diagnostic scan to confirm the P0158 code and check for any additional codes that may provide further insight into the issue.
  2. Visual Inspection: Conduct a visual inspection of the wiring and connectors associated with Bank 2, Sensor 2 for signs of damage, corrosion, or loose connections.
  3. Sensor Replacement: If the oxygen sensor is determined to be faulty, replace it with a new, OEM-quality sensor to ensure proper function.
  4. Repair Wiring Issues: If damaged wiring or connectors are found, repair or replace them as necessary to restore proper electrical flow.
  5. Clear Codes and Test Drive: After repairs, clear the DTCs from the ECM and perform a test drive to ensure the issue has been resolved and that the check engine light does not reappear.

Cost to Fix P0158 2018 GMC Sierra

** The cost to repair a P0158 code can vary widely based on the specific issue identified. On average, replacing an oxygen sensor can cost between $150 to $300, including parts and labor. If wiring repairs are necessary, costs can increase significantly, potentially reaching $500 or more depending on the extent of the damage. Labor rates typically range from $80 to $150 per hour, with metropolitan areas or dealerships often charging higher rates. Independent shops may offer lower rates. It is advisable to obtain a detailed estimate from local repair shops to get a more precise cost based on your specific vehicle and location.

Tech Notes for P0158 2018 GMC Sierra

Replacing the Rear Heated Oxygen Sensor (HO2S) Bank 2 usually takes care of the problem.











User Submitted Video

Need more information about the P0158 2018 GMC Sierra code?

Need more information on how to fix the P0158 2018 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0158 2018 GMC Sierra code diagnosed by a professional: Find a repair shop in your area

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0158 2018 GMC Sierra Code

No Frequently Asked Questions about P0158 2018 GMC Sierra Code found.

Discuss the causes and fixes for P0158 2018 GMC Sierra OBDII Code

Code P0158 2018 GMC Sierra comments

No comments found for this page.