P1273 Infiniti Code - Air Fuel Ratio Sensor 1 Bank 1 Lean Shift Monitoring
Quick Answer
The Air Fuel Ratio (A/F) sensor is a planar dual-cell limit current sensor. Common causes include Faulty Air fuel ratio (A/F) Sensor 1 Bank 1, Air fuel ratio (A/F) Sensor 1 Bank 1 harness is open or shorted, Air fuel ratio (A/F) Sensor 1 Bank 1 circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P1273 Infiniti indicates Air Fuel Ratio Sensor 1 Bank 1 Lean Shift Monitoring.
- Common causes
- Common causes include Faulty Air fuel ratio (A/F) Sensor 1 Bank 1, Air fuel ratio (A/F) Sensor 1 Bank 1 harness is open or shorted, Air fuel ratio (A/F) Sensor 1 Bank 1 circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P1273 Infiniti Description
The sensor is capable of precise measurement λ= 1, but also in the lean and rich range. Together with its control electronics, the sensor outputs a clear, continuous signal throughout a wide λ range (0.7 < λ < air).
The exhaust gas components diffuse through the diffusion gap at the electrode of the oxygen pump and Nernst concentration cell, where they are brought to thermodynamic balance.
An electronic circuit controls the pump current through the oxygen-pump cell so that the composition of the exhaust gas in the diffusion gap remains constant at λ = 1. Therefore, the A/F sensor is able to indicate air/fuel ratio by this pumping of current. In addition, a heater is integrated in the sensor to ensure the required operating temperature of 700 - 800 C (1,292 - 1,472 F).
What are the Possible Causes of the DTC P1273 Infiniti?
- Faulty Air fuel ratio (A/F) Sensor 1 Bank 1
- Air fuel ratio (A/F) Sensor 1 Bank 1 harness is open or shorted
- Air fuel ratio (A/F) Sensor 1 Bank 1 circuit poor electrical connection
- Fuel pressure
- Faulty Fuel injector
- Faulty Air Flow Meter
How to Fix the DTC P1273 Infiniti?
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
There is a Factory Service Bulletin for the following Infiniti models:
2003-2012 Infiniti FX
2002 Infiniti G20
2003-2006 Infiniti G35 Sedan
2003-2007 Infiniti G35 Coupe
2006-2012 Infiniti G37 Sedan
2008-2012 Infiniti G37 Coupe
2002-2004 Infiniti I35
2004-2012 Infiniti M
2002-2006 Infiniti Q45
2002-2003 Infiniti QX4
2004-2012 Infiniti QX56
Infiniti Factory Service Bulletin OBDII Code P1273
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P1273 Infiniti 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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Need Help with the Code?
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Frequently Asked Questions about P1273 Infiniti Code
No Frequently Asked Questions about P1273 Infiniti Code found.
Discuss the causes and fixes for P1273 Infiniti OBDII Code
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I will like to know does Bank 1 means (upstream or downstream left and right) cos am having thesame issue with my mum infinite FX 2005 too and its says Air Flow System Sensor Failure Bank 1
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What does bank mean: https://www.autocodes.com/a...
Do you have an FX45 or FX35?
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I HAVE THE SAME FX35 HAVING SAME ISSUE
CAN YOU HELP PLEASE?smoke tested no leaks except waay in the back after both sensors from muffler
new spark plugs and new a/f sensor
car runs smooth though -
If you already replaced the A/F sensor and there are no leaks, then the next step is to clean or replace the Mass Air Flow (MAF) sensor.
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