AutoCodes – Nissan – P0420 2004 Nissan Murano

P0420 2004 Nissan Murano Code - Catalyst System Efficiency Below Threshold Bank 1

Quick Answer

The Engine Control Module (ECM) monitors the switching frequency ratio of heated oxygen sensors 1 (front O2 sensor) and heated oxygen sensors 2 (rear O2 sensor). Common causes include Faulty Three-way Catalyst Converter Bank 1, Exhaust Tube, Intake Air Leaks. 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: P0420 2004 Nissan Murano indicates Catalyst System Efficiency Below Threshold Bank 1.
Common causes: Common causes include Faulty Three-way Catalyst Converter Bank 1, Exhaust Tube, Intake Air Leaks.
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.

Save to My Repairs Step-by-Step Diagnostic Guide My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 16,042

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 Aug 20, 2020

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P0420 2004 Nissan Murano Description

The Engine Control Module (ECM) monitors the switching frequency ratio of heated oxygen sensors 1 (front O2 sensor) and heated oxygen sensors 2 (rear O2 sensor).
A three way catalyst converter (Manifold) with high oxygen storage capacity will indicate a low switching frequency of heated oxygen sensor 2. As oxygen storage capacity decreases, the heated oxygen sensor 2 switching frequency will increase.
When the frequency ratio of heated oxygen sensors 1 and 2 approaches a specified limit value, the three way catalyst malfunction is diagnosed.

OBDII Code P0420 2004 Nissan Murano - Catalyst System Efficiency Below Threshold Bank 1 - AutoCodes.com — P0420 2004 Nissan Murano Code - Catalyst System Efficiency Below Threshold Bank 1

What does this mean?

What are the Possible Causes of the DTC P0420 2004 Nissan Murano?

Faulty Three-way Catalyst Converter Bank 1
Exhaust Tube
Intake Air Leaks
Faulty Oxygen (O2) Sensor
Faulty Fuel injector(s)
Leaking Fuel Injector (s)
Faulty Spark plugs
Improper Ignition Timing
Faulty Engine Control Module (ECM)
Dirty Air Filter

How to Fix the DTC P0420 2004 Nissan Murano?

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

As the code description implies the P0420 code means that the vehicle's control module has detected that the three-way catalytic converter is not working properly (is not as efficient as the factory is expecting). Replacing the oxygen (O2) sensors may sometimes fix the code, but in most cases, the catalytic convert needs to be replaced to correct the problem. If the P0420 code is combined with other codes, try fixing the other codes first.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0420 2004 Nissan Murano 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 P0420 2004 Nissan Murano code?

Need more information on how to fix the P0420 2004 Nissan Murano code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0420 2004 Nissan Murano code diagnosed by a professional: Find a repair shop in your area

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 P0420 2004 Nissan Murano Code

1. What are the common symptoms of OBDII code P0420 in a 2004 Nissan Murano?

- The common symptoms include reduced fuel efficiency, rough idling, and the illumination of the check engine light.

2. What does the OBDII code P0420 indicate in a 2004 Nissan Murano?

- The code P0420 indicates that the Catalyst System Efficiency is below the threshold on Bank 1 of the engine.

3. What are the possible causes of OBDII code P0420 in a 2004 Nissan Murano?

- Common causes include a faulty catalytic converter, oxygen sensor issues, exhaust leaks, or engine misfires.

4. Can a bad oxygen sensor trigger the OBDII code P0420 in a 2004 Nissan Murano?

- Yes, a malfunctioning oxygen sensor can contribute to triggering the P0420 code by providing inaccurate data to the engine control module.

5. How can I diagnose and repair the OBDII code P0420 in my 2004 Nissan Murano?

- Diagnosis involves checking the oxygen sensors, inspecting the catalytic converter, and looking for exhaust leaks. Repair may involve replacing the catalytic converter or fixing any underlying issues.

6. Is it safe to continue driving with the OBDII code P0420 in a 2004 Nissan Murano?

- It is generally safe to drive with the P0420 code, but it is recommended to address the issue promptly to prevent further damage to the catalytic converter and ensure optimal vehicle performance.

7. Can a clogged catalytic converter cause the OBDII code P0420 in a 2004 Nissan Murano?

- Yes, a clogged or failing catalytic converter can trigger the P0420 code due to reduced efficiency in converting harmful emissions.

8. How much does it typically cost to repair the OBDII code P0420 in a 2004 Nissan Murano?

- The cost of repair can vary depending on the underlying issue, but replacing a catalytic converter can range from $500 to $2,500, including parts and labor.

9. Are there any DIY tips for addressing the OBDII code P0420 in a 2004 Nissan Murano?

- DIY tips may include checking for exhaust leaks, cleaning or replacing oxygen sensors, and using fuel additives to help clean the catalytic converter.

10. How often should I have my 2004 Nissan Murano's exhaust system inspected to prevent the OBDII code P0420?

- It is recommended to have your exhaust system inspected annually or during routine maintenance to catch any potential issues early and prevent the P0420 code from occurring.