P0138 Nissan Code - HO2S12 Circuit High Voltage
Quick Answer
The Heated Oxygen Sensor 2 (HO2S) (Rear O2 Sensor), after three way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. Common causes include Faulty Rear Heated Oxygen Sensor Bank 1, Rear Heated Oxygen Sensor Bank 1 harness is open or shorted, Rear Heated Oxygen Sensor Bank 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
- P0138 Nissan indicates HO2S12 Circuit High Voltage.
- Common causes
- Common causes include Faulty Rear Heated Oxygen Sensor Bank 1, Rear Heated Oxygen Sensor Bank 1 harness is open or shorted, Rear Heated Oxygen Sensor Bank 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 P0138 Nissan Description
What are the Possible Causes of the DTC P0138 Nissan?
- Faulty Rear Heated Oxygen Sensor Bank 1
- Rear Heated Oxygen Sensor Bank 1 harness is open or shorted
- Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection
- Intake air leaks
- Exhaust gas leaks
- Inappropriate fuel pressure
- Faulty fuel injectors
How to Fix the DTC P0138 Nissan?
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 P0138 Nissan 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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Information for Specific Nissan Models
- P0138 2002 Nissan Altima Sedan — HO2S12 Circuit High Voltage
- P0138 2003 Nissan Altima Sedan — HO2S12 Circuit High Voltage
- P0138 2004 Nissan Altima Sedan — HO2S12 Circuit High Voltage
- P0138 2005 Nissan Altima Sedan — HO2S12 Circuit High Voltage
- P0138 2006 Nissan Altima Sedan — HO2S12 Circuit High Voltage
- P0138 2008 Nissan Altima Sedan — HO2S12 Circuit High Voltage
- P0138 2009 Nissan Altima Sedan — HO2S12 Circuit High Voltage
- P0138 2010 Nissan Altima Sedan — HO2S12 Circuit High Voltage
- P0138 2011 Nissan Altima Sedan — HO2S12 Circuit High Voltage
- P0138 2012 Nissan Altima Sedan — HO2S12 Circuit High Voltage
- P0138 2004 Nissan Maxima — HO2S12 Circuit High Voltage
- P0138 2005 Nissan Maxima — HO2S12 Circuit High Voltage
- P0138 2006 Nissan Maxima — HO2S12 Circuit High Voltage
- P0138 2007 Nissan Maxima — HO2S12 Circuit High Voltage
- P0138 2008 Nissan Maxima — HO2S12 Circuit High Voltage
- P0138 2005 Nissan Pathfinder — HO2S12 Circuit High Voltage
- P0138 2006 Nissan Pathfinder — HO2S12 Circuit High Voltage
- P0138 2007 Nissan Pathfinder — HO2S12 Circuit High Voltage
- P0138 2008 Nissan Pathfinder — HO2S12 Circuit High Voltage
- P0138 2009 Nissan Pathfinder — HO2S12 Circuit High Voltage
- P0138 2010 Nissan Pathfinder — HO2S12 Circuit High Voltage
- P0138 2011 Nissan Pathfinder — HO2S12 Circuit High Voltage
- P0138 2012 Nissan Pathfinder — HO2S12 Circuit High Voltage
- P0138 2008 Nissan Rogue — HO2S12 Circuit High Voltage
- P0138 2009 Nissan Rogue — HO2S12 Circuit High Voltage
- P0138 2010 Nissan Rogue — HO2S12 Circuit High Voltage
- P0138 2011 Nissan Rogue — HO2S12 Circuit High Voltage
- P0138 2012 Nissan Rogue — HO2S12 Circuit High Voltage
- P0138 2013 Nissan Rogue — HO2S12 Circuit High Voltage
- P0138 2002 Nissan Sentra — HO2S12 Circuit High Voltage
- P0138 2003 Nissan Sentra — HO2S12 Circuit High Voltage
- P0138 2004 Nissan Sentra — HO2S12 Circuit High Voltage
- P0138 2005 Nissan Sentra — HO2S12 Circuit High Voltage
- P0138 2006 Nissan Sentra — HO2S12 Circuit High Voltage
- P0138 2007 Nissan Sentra — HO2S12 Circuit High Voltage
- P0138 2008 Nissan Sentra — HO2S12 Circuit High Voltage
- P0138 2009 Nissan Sentra — HO2S12 Circuit High Voltage
- P0138 2010 Nissan Sentra — HO2S12 Circuit High Voltage
- P0138 2011 Nissan Sentra — HO2S12 Circuit High Voltage
- P0138 2012 Nissan Sentra — HO2S12 Circuit High Voltage
Frequently Asked Questions about P0138 Nissan Code
1. What are the common symptoms of OBDII code P0138 in a Nissan vehicle?
- Common symptoms of code P0138 include poor fuel economy, loss of power, rough idling, and the illumination of the Check Engine Light.
2. What does the OBDII code P0138 "HO2S12 Circuit High Voltage" mean in a Nissan?
- The code P0138 indicates that the oxygen sensor (O2 sensor) located in bank 1 sensor 2 is reading a high voltage signal, potentially due to a malfunction.
3. What are the possible causes of OBDII code P0138 in a Nissan?
- Common causes of code P0138 include a faulty oxygen sensor, wiring issues in the HO2S12 circuit, an exhaust leak near the sensor, or an engine running too rich.
4. How can I diagnose the OBDII code P0138 in my Nissan?
- To diagnose code P0138, you can use an OBDII scanner to read the code, inspect the wiring and connections of the HO2S12 sensor, and perform tests to determine if the sensor is functioning correctly.
5. Can I continue driving my Nissan with the OBDII code P0138 present?
- It is not recommended to continue driving with code P0138 present, as it can lead to further damage to your vehicle's engine and emissions system. It's best to address the issue promptly.
6. Is it safe to clear the OBDII code P0138 in my Nissan without fixing the underlying issue?
- Clearing the code without addressing the underlying problem will only temporarily turn off the Check Engine Light. The issue causing code P0138 will persist and may lead to more serious problems if left unresolved.
7. How can I repair OBDII code P0138 in my Nissan?
- Repairing code P0138 may involve replacing the HO2S12 oxygen sensor, repairing or replacing damaged wiring, fixing any exhaust leaks, or addressing issues that may be causing the engine to run too rich.
8. Can a DIY enthusiast fix the OBDII code P0138 in a Nissan?
- Depending on your mechanical skills and knowledge, it may be possible for a DIY enthusiast to address code P0138 by replacing the oxygen sensor or fixing wiring issues. However, professional help may be needed for more complex repairs.
9. Will fixing the OBDII code P0138 improve my Nissan's fuel efficiency?
- Addressing code P0138 and ensuring the oxygen sensor is functioning properly can help improve fuel efficiency by allowing the engine to operate optimally and maintain the correct air-fuel ratio.
10. How much does it cost to repair OBDII code P0138 in a Nissan?
- The cost of repairing code P0138 in a Nissan can vary depending on the underlying issue, the cost of parts, and the labor rates of the repair shop. It's recommended to obtain quotes from different mechanics for an accurate estimate.
Discuss the causes and fixes for P0138 Nissan OBDII Code
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I have a 2000 maxima with a p0138 code o2 sensor (bank 1 sensor 2) can you direct me to its location. Please! Thank you!
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See attached image for location of the Rear (Sensor 2) Bank 1 Oxygen sensor
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Hello. I need your help! after replacing the o2 sensor for code P0138 (bank 1 sensor 2), after driving it for 40 miles, engine light came on. I scanned it and got p0158 (bank 2 sensor 2) is there something else i should be checking and is this normal ?
Thank you! -
Unfortunately I'm not aware of any problems that could cause the other O2 sensor to fail at the same time. Make sure there no exhaust leaks around the O2 sensors.
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