AutoCodes – Generic – P1147

P1147 Code - Heated Oxygen Sensor 2 Maximum Voltage Monitoring Bank 1

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 heated oxygen (O2) sensor 2 (rear), Intake air leaks, Heated oxygen (O2) sensor 2 (rear) harness is open or shorted. 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: P1147 indicates Heated Oxygen Sensor 2 Maximum Voltage Monitoring Bank 1.
Common causes: Common causes include Faulty heated oxygen (O2) sensor 2 (rear), Intake air leaks, Heated oxygen (O2) sensor 2 (rear) harness is open or shorted.
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 36,328

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 02, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1147 Description

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. 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 P1147 - Heated Oxygen Sensor 2 Maximum Voltage Monitoring Bank 1 - AutoCodes.com — P1147 Code - Heated Oxygen Sensor 2 Maximum Voltage Monitoring Bank 1

What does this mean?

What are the Possible Causes of the DTC P1147?

Faulty heated oxygen (O2) sensor 2 (rear)
Intake air leaks
Heated oxygen (O2) sensor 2 (rear) harness is open or shorted
Heated oxygen (O2) sensor 2 (rear) circuit poor electrical connection
Inappropriate fuel pressure
Faulty fuel injectors

How to Fix the DTC P1147?

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 P1147 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 P1147 code?

Need more information on how to fix the P1147 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1147 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P1147 Audi — HO2S21 System Too Lean
P1147 Hyundai — Accelerator Position Sensor 1 Malfunction
P1147 Infiniti — Heated Oxygen Sensor 2 Maximum Voltage Monitoring Bank 1
P1147 Nissan — Heated Oxygen Sensor 2 Maximum Voltage Monitoring Bank 1
P1147 Volkswagen — HO2S21 System Too Lean

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 P1147 Code

1. What are the common symptoms of OBDII code P1147 (Heated Oxygen Sensor 2 Maximum Voltage Monitoring Bank 1)?

The common symptoms include poor fuel economy, rough idling, and a noticeable decrease in engine performance.

2. What are the possible causes of OBDII code P1147?

Potential causes of this code include a faulty oxygen sensor, a wiring issue in the oxygen sensor circuit, or an exhaust leak near the sensor.

3. How can I diagnose the root cause of OBDII code P1147?

To diagnose the issue, you can use an OBDII scanner to read the code and inspect the oxygen sensor and its related wiring for any visible damage or corrosion.

4. Can I continue driving with OBDII code P1147 triggered?

It is not recommended to drive with this code triggered, as it can lead to further damage to the engine and emissions system over time.

5. How can I repair OBDII code P1147?

Repairing this code typically involves replacing the faulty oxygen sensor, fixing any wiring issues, and clearing the code with an OBDII scanner.

6. Is it safe to ignore OBDII code P1147?

Ignoring this code can lead to decreased fuel efficiency and potential damage to the catalytic converter, so it is best to address the issue promptly.

7. How much does it cost to fix OBDII code P1147?

The cost of fixing this code can vary depending on the root cause, but it typically ranges from $100 to $300 for parts and labor.

8. Can a DIY enthusiast repair OBDII code P1147?

If you have experience working on cars and access to the necessary tools, you may be able to repair this code yourself by replacing the oxygen sensor and checking the wiring.

9. How long does it take to repair OBDII code P1147?

The repair time can vary depending on the complexity of the issue, but it usually takes around 1-2 hours to replace the oxygen sensor and clear the code.

10. Will OBDII code P1147 cause my vehicle to fail an emissions test?

Yes, having this code triggered can cause your vehicle to fail an emissions test, as it indicates a problem with the emissions control system.