P0051 2018 GMC Sierra Code - HO2S Heater Control Circuit Low Voltage Bank 2 Sensor 1
Quick Answer
Heated Oxygen Sensors (HO2S) are used for fuel control and post catalyst monitoring. Common causes include Faulty Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1, Heated Oxygen Sensor Bank 2 Sensor 1 harness is open shorted, Heated Oxygen Sensor Bank 2 Sensor 1 circuit poor electrical connection. 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
- P0051 2018 GMC Sierra indicates HO2S Heater Control Circuit Low Voltage Bank 2 Sensor 1.
- Common causes
- Common causes include Faulty Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1, Heated Oxygen Sensor Bank 2 Sensor 1 harness is open shorted, Heated Oxygen Sensor Bank 2 Sensor 1 circuit poor electrical connection.
- 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.
Code P0051 2018 GMC Sierra Description
The Diagnostic Trouble Code (DTC) will be set when the ECM detects a short to ground in the heater output low side driver circuit of the heated oxygen sensor when the heater is commanded OFF for greater than 5 s.
What are the Possible Causes of the DTC P0051 2018 GMC Sierra?
- Faulty Heated Oxygen Sensor (H2OS) Bank 2 Sensor 1
- Heated Oxygen Sensor Bank 2 Sensor 1 harness is open shorted
- Heated Oxygen Sensor Bank 2 Sensor 1 circuit poor electrical connection
- Heated Oxygen Sensor Bank 2 Sensor 1 fuse
- Faulty Engine Control Module (ECM)
How to Fix the DTC P0051 2018 GMC Sierra?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0051 2018 GMC Sierra code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Frequently Asked Questions about P0051 2018 GMC Sierra Code
What does the OBDII code P0051 mean for a 2018 GMC Sierra?
The P0051 code indicates a low voltage issue in the heater control circuit for the Bank 2 Sensor 1 oxygen sensor.
What are the symptoms of code P0051 on a 2018 GMC Sierra?
Common symptoms include increased fuel consumption, poor engine performance, and the check engine light turning on.
What causes the P0051 code to appear?
Possible causes include a faulty oxygen sensor, damaged wiring or connectors, a blown fuse, or issues with the PCM.
How can I diagnose the P0051 code on my 2018 GMC Sierra?
Check the oxygen sensor wiring, connectors, and fuse for damage. Use a multimeter to test the heater circuit for proper voltage.
What is Bank 2 Sensor 1 in a 2018 GMC Sierra?
Bank 2 refers to the side of the engine without cylinder 1, and Sensor 1 is the upstream oxygen sensor located before the catalytic converter.
Can I drive my 2018 GMC Sierra with a P0051 code?
Driving with this code may lead to reduced fuel efficiency and engine performance, but it’s typically not an immediate safety concern.
How do I fix the P0051 code on a 2018 GMC Sierra?
Repairs may include replacing the oxygen sensor, repairing wiring or connectors, or checking and replacing a blown fuse.
How much does it cost to repair a P0051 code?
Repair costs can range from $150 to $300, depending on whether the oxygen sensor or wiring needs replacement.
Will clearing the P0051 code fix the issue?
Clearing the code will not resolve the underlying problem; proper diagnosis and repair are required to prevent the code from returning.
What tools are needed to fix a P0051 code?
You’ll need an OBDII scanner, a multimeter for electrical tests, and basic hand tools to replace the oxygen sensor or repair wiring.
Discuss the causes and fixes for P0051 2018 GMC Sierra OBDII Code
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