AutoCodes – Honda – P1172 2009 Honda Accord

P1172 2009 Honda Accord Code - Rear A/F Sensor Bank 1 Sensor 1 Circuit Out Of Range High

Quick Answer

The Air/Fuel Ratio (A/F) sensor 1 is installed in the exhaust system and detects oxygen content in the exhaust gas. Common causes include Faulty Air/Fuel Ratio Bank 1 Sensor 1, Air/Fuel Ratio Bank 1 Sensor 1 harness is open or shorted, Air/Fuel Ratio Bank 1 Sensor 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: P1172 2009 Honda Accord indicates Rear A/F Sensor Bank 1 Sensor 1 Circuit Out Of Range High.
Common causes: Common causes include Faulty Air/Fuel Ratio Bank 1 Sensor 1, Air/Fuel Ratio Bank 1 Sensor 1 harness is open or shorted, Air/Fuel Ratio Bank 1 Sensor 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.

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Code Popularity 2,971

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on May 16, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1172 2009 Honda Accord Description

The Air/Fuel Ratio (A/F) sensor 1 is installed in the exhaust system and detects oxygen content in the exhaust gas. The A/F sensor transmits output voltage to the Engine Control Module (ECM). A heater for the sensor element is embedded in the A/F sensor (sensor 1). It is activated and heats the sensor to stabilize and speed the detection of oxygen content by controlling current flowing through the heater. An increase in the current levels off as the applied voltage to the element electrode reaches a certain range because the amount of oxygen which is led through the diffusion layer is limited. The current amperage is proportional to oxygen content in the exhaust gas, so the air/fuel ratio is detected by the measurement of the current amperage. The ECM compares a set target air/fuel ratio with the detected air/fuel ratio and controls the fuel injection timing.
If the A/F sensor (sensor 1) voltage is low, the air/fuel ratio is lean, and the ECM uses A/F feedback control to issue a Rich command. If the A/F sensor (sensor 1) voltage is high, the air/fuel ratio is rich, and the ECM uses A/F feedback control to issue a Lean command.

OBDII Code P1172 2009 Honda Accord - Rear A/F Sensor Bank 1 Sensor 1 Circuit Out Of Range High - AutoCodes.com — P1172 2009 Honda Accord Code - Rear A/F Sensor Bank 1 Sensor 1 Circuit Out Of Range High

What does this mean?

What are the Possible Causes of the DTC P1172 2009 Honda Accord?

Faulty Air/Fuel Ratio Bank 1 Sensor 1
Air/Fuel Ratio Bank 1 Sensor 1 harness is open or shorted
Air/Fuel Ratio Bank 1 Sensor 1 circuit poor electrical connection

How to Fix the DTC P1172 2009 Honda Accord?

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 is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1172 2009 Honda Accord 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.

Need more information about the P1172 2009 Honda Accord code?

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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 P1172 2009 Honda Accord Code

1. What are the common symptoms of OBDII code P1172 on a 2009 Honda Accord related to the Rear A/F Sensor Bank 1 Sensor 1 circuit being out of range high?

- Common symptoms include poor fuel economy, rough idling, loss of power, and the illuminated check engine light.

2. What are the possible causes of OBDII code P1172 on a 2009 Honda Accord?

- The code P1172 can be triggered by a faulty rear Air/Fuel (A/F) sensor Bank 1 Sensor 1, wiring issues, or a problem with the engine control module (ECM).

3. How do I diagnose the issue causing OBDII code P1172 on my 2009 Honda Accord?

- Diagnosing the issue involves checking the rear A/F sensor Bank 1 Sensor 1 for proper operation, inspecting the wiring for damage or loose connections, and scanning the ECM for fault codes.

4. Can I continue driving my 2009 Honda Accord with OBDII code P1172 present?

- It is not recommended to drive the vehicle with the code P1172 present, as it can lead to poor engine performance and potentially cause damage to other components.

5. How can I repair OBDII code P1172 on a 2009 Honda Accord related to the Rear A/F Sensor Bank 1 Sensor 1 circuit being out of range high?

- The repair typically involves replacing the rear A/F sensor Bank 1 Sensor 1 if it is found to be faulty, repairing any damaged wiring, and clearing the fault codes.

6. Is it possible to reset the OBDII code P1172 on a 2009 Honda Accord without fixing the issue?

- While you can clear the fault code using a scan tool, the underlying issue causing the code will need to be addressed to prevent it from recurring.

7. How much does it cost to fix OBDII code P1172 on a 2009 Honda Accord at a repair shop?

- The cost of fixing the code P1172 can vary depending on the exact cause of the issue, but it typically involves diagnostic labor charges, parts costs for the sensor or wiring repairs, and any necessary programming.

8. Can a DIY enthusiast with basic automotive knowledge fix OBDII code P1172 on a 2009 Honda Accord?

- Depending on the exact cause, a DIY enthusiast may be able to fix the code P1172 by replacing the rear A/F sensor Bank 1 Sensor 1 or addressing any wiring issues with the proper tools and instructions.

9. How long does it take to repair OBDII code P1172 on a 2009 Honda Accord?

- The repair time can vary based on the cause of the issue and the expertise of the technician, but it typically takes a few hours to diagnose and fix the problem.

10. Will fixing OBDII code P1172 on a 2009 Honda Accord improve the vehicle's overall performance?

- Yes, addressing the code P1172 and restoring the proper operation of the rear A/F sensor Bank 1 Sensor 1 can help improve fuel efficiency, engine performance, and overall drivability of the vehicle.