AutoCodes – Nissan – P0139 2010 Nissan Altima Sedan

P0139 2010 Nissan Altima Sedan Code - HO2S12 Slow Response

Quick Answer

The Heated Oxygen Sensor 2 (HO2S), 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: P0139 2010 Nissan Altima Sedan indicates HO2S12 Slow Response.
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.

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Code Popularity 3,791

How popular is this code, among other codes? Low

Repair Importance Level

Moderate (Service soon) (2 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Apr 12, 2019

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0139 2010 Nissan Altima Sedan Description

The Heated Oxygen Sensor 2 (HO2S), after three way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. For optimum catalyst operation, the air fuel mixture (air-fuel ratio) must be maintained near the ideal stoichiometric ratio. The HO2S output voltage changes suddenly in the vicinity of the stoichiometric ratio. The Engine Control Module (ECM) adjusts the fuel injection time so that the air-fuel ratio is nearly stoichiometric. The HO2S generates a voltage between 0.1 and 0.9 V in response to oxygen in the exhaust gas. If the oxygen in the exhaust gas increases, the air-fuel ratio becomes Lean. The ECM interprets Lean when the HO2S voltage is below 0.45 V. If the oxygen in the exhaust gas decreases, the air-fuel ratio becomes Rich. The ECM interprets Rich when the HO2S voltage is above 0.45 V.

OBDII Code P0139 2010 Nissan Altima Sedan - HO2S12 Slow Response - AutoCodes.com — P0139 2010 Nissan Altima Sedan Code - HO2S12 Slow Response

What does this mean?

What are the Possible Causes of the DTC P0139 2010 Nissan Altima Sedan?

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
Inappropriate fuel pressure
Faulty fuel injectors
Intake air leaks may be faulty
Exhaust gas leaks

How to Fix the DTC P0139 2010 Nissan Altima Sedan?

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.

What does this mean?

Code Tech Notes

Replacing the Rear Heated Oxygen Sensor Bank 1 usually takes care of the problem.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0139 2010 Nissan Altima Sedan 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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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 P0139 2010 Nissan Altima Sedan Code

1. What does OBDII code P0139 on a 2010 Nissan Altima Sedan mean?

This code, HO2S12 Slow Response, indicates a slow response from the downstream oxygen sensor (HO2S12) in bank 1 sensor 2 in the exhaust system of the vehicle.

2. What are the common symptoms of OBDII code P0139 in a 2010 Nissan Altima Sedan?

Common symptoms include decreased fuel efficiency, rough idling, engine hesitation, and potential stalling.

3. What are the possible causes of OBDII code P0139 in a 2010 Nissan Altima Sedan?

Potential causes include a faulty oxygen sensor, wiring issues in the oxygen sensor circuit, exhaust leaks, or issues with the engine's air-fuel ratio.

4. How serious is OBDII code P0139 in a 2010 Nissan Altima Sedan?

While the vehicle may still be operable with this code, ignoring it can lead to decreased fuel efficiency and potential damage to other components over time.

5. Can I drive my 2010 Nissan Altima Sedan with OBDII code P0139?

It is generally not recommended to drive the vehicle for an extended period with this code present, as it can impact the engine's performance and fuel efficiency.

6. How can I diagnose OBDII code P0139 in my 2010 Nissan Altima Sedan?

Diagnosis typically involves inspecting the oxygen sensor, checking for wiring issues, and ensuring there are no exhaust leaks affecting sensor performance.

7. How can I repair OBDII code P0139 in my 2010 Nissan Altima Sedan?

Common repairs include replacing the downstream oxygen sensor, repairing any damaged wiring, fixing exhaust leaks, and addressing issues with the air-fuel ratio.

8. Will resetting the OBDII code P0139 on my 2010 Nissan Altima Sedan make it go away?

Resetting the code may temporarily clear the warning light, but if the underlying issue is not resolved, the code is likely to reappear after driving the vehicle for a while.

9. Can a DIY enthusiast fix OBDII code P0139 in a 2010 Nissan Altima Sedan?

Depending on the skill level and tools available, some DIY enthusiasts may be able to replace the oxygen sensor or address wiring issues related to this code.

10. How much does it cost to repair OBDII code P0139 in a 2010 Nissan Altima Sedan?

Costs for repairing this code can vary significantly based on the specific issue, but expect to pay for parts like the oxygen sensor and potential labor costs if professional help is needed.