FAULTBASE
NEWSASKCars
© 2025 FAULTBASE
All rights reserved.
v2.0.0 • Production
ContactPrivacyImpressum
Home/Cars/Honda/CR-V/6th Gen (2023-Present)/how to fix P0420 code on Honda CR-V Sixth Generation (2023-present)

how to fix P0420 code on Honda CR-V Sixth Generation (2023-present)

Honda CR-V 6th Gen (2023-Present)

Severity: highDifficulty: mediumError Code: P04202-4 hours
3 min read
517 words

⚠️ Safety Warning

This issue requires immediate attention. If you are not experienced with automotive repairs, consult a professional mechanic. Working on critical systems can be dangerous.

Problem Statement

Learn how to diagnose and fix P0420 code in Honda CR-V (2023-present). Step-by-step guide with diagnostic procedures and repair instructions.

Error Code
P0420
Component
Exhaust System
Repair Time
2-4 hours

Safety Warnings

  • ⚠Disconnect battery before working on electrical systems.
  • ⚠Allow the exhaust system to cool before handling components.

Symptoms

  • •Check engine light illuminated
  • •Decreased fuel efficiency
  • •Poor engine performance
  • •Failure of emissions test
  • •Unusual odors from exhaust

Diagnostic Steps

  1. 1Scan for error codes using an OBD-II scanner to confirm the P0420 code and check for any related codes.
  2. 2Inspect the exhaust system for leaks or damage that could affect the catalytic converter's performance.
  3. 3Check the oxygen sensors (upstream and downstream) for proper operation using a multimeter.
  4. 4Measure the temperature difference between the inlet and outlet of the catalytic converter to assess its efficiency.
  5. 5Inspect for any previous repairs or modifications that may have affected the exhaust system.
  6. 6Review the vehicle's maintenance history for recent work that could relate to the issue.

Solution

Solution

1. Preparation

  • Gather necessary tools and parts.
  • Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Oxygen Sensors

  • Tools Required: O2 sensor socket, ratchet, torque wrench
  • Sub-steps:
    1. Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
    2. Using the O2 sensor socket, carefully remove the upstream oxygen sensor.
    3. Install the new oxygen sensor and torque it to the manufacturer's specification (typically around 30 lb-ft).
    4. Repeat for the downstream oxygen sensor if needed.

3. Inspect and Replace Catalytic Converter

  • Tools Required: Socket set, jack stands, exhaust pipe cutter (if necessary)
  • Sub-steps:
    1. Raise the vehicle securely using jack stands.
    2. Inspect the catalytic converter for physical damage or blockage.
    3. If replacement is necessary, disconnect the exhaust pipes from the catalytic converter using a socket set.
    4. Remove any bolts or clamps securing the catalytic converter.
    5. Install the new catalytic converter, ensuring proper alignment and sealing of joints.
    6. Torque all bolts to the manufacturer's specification.

4. Reconnect Battery and Clear Codes

  • Reconnect the negative battery terminal.
  • Use the OBD-II scanner to clear the P0420 code and any other related codes.

Verification

After completing the repair, verify that the issue has been resolved:

  • Test the affected component to ensure it functions correctly
  • Check for any error codes or warning lights
  • Monitor the vehicle for a few days to ensure the issue does not recur

Prevention Tips

To prevent this issue from occurring again:

  • •Follow the manufacturer's recommended maintenance schedule
  • •Address warning signs early before they develop into major issues
  • •Use quality parts and fluids recommended for your vehicle
  • •Keep detailed records of all repairs and maintenance

Tools & Equipment Required

  • OBD-II scanner
  • O2 sensor socket
  • Ratchet
  • Torque wrench
  • Socket set
  • Jack stands
  • Exhaust pipe cutter

Parts Required

  • Upstream oxygen sensor
  • Downstream oxygen sensor
  • Catalytic converter

Additional Information

Error CodeP0420
Component

Exhaust System

Repair Time

2-4 hours

Difficulty

medium

Severity

high

Tools

7 items

Parts

3 items

Related Faults

Discover similar issues

  1. how to fix Honda CR-V Fifth Generation (2017-2022) transmission slipping

    Learn how to diagnose and fix transmission slipping in Honda CR-V Fifth Generation (2017-2022). Step-by-step guide with diagnostic procedures and repa...

    Component:Transmission
    Symptoms
    • •Engine RPM increases without corresponding vehicle acceleration
    • •Delayed or harsh shifting between gears
    • +{count} more
  2. my Honda CR-V Fifth Generation (2017-2022) has poor acceleration what’s the reason

    Learn how to diagnose and fix poor acceleration in Honda CR-V (2017-2022). Step-by-step guide with symptoms, diagnostic steps, and repair instructions...

    Component:Engine
    Symptoms
    • •Check engine light illuminated
    • •Hesitation during acceleration
    • +{count} more
  3. how to troubleshoot the door ajar warning light in my Honda CR-V Sixth Generation (2023-present)

    Learn how to troubleshoot the door ajar warning light in your Honda CR-V (2023-present). Step-by-step guide with diagnostic steps and solutions.

    Component:Electrical
    Symptoms
    • •Door ajar warning light remains on despite all doors being securely closed
    • •Interior lights remain on when the vehicle is off
    • +{count} more
  4. my Honda CR-V's check engine light keeps coming on, what could be wrong?

    Discover how to diagnose and fix check engine light issues in Honda CR-V. Step-by-step guide with symptoms, diagnostic steps, and repair instructions.

    Component:Engine
    Symptoms
    • •Check engine light illuminated
    • •Rough idle or engine stalling
    • +{count} more
  5. my Honda CR-V makes a grinding noise when I turn the steering wheel what's wrong

    Learn how to diagnose and fix grinding noise when steering in Honda CR-V. Step-by-step guide with diagnostic procedures and repair instructions.

    Component:Steering
    Symptoms
    • •Grinding noise when steering
    • •Difficulty steering or tightness in the steering wheel
    • +{count} more
  6. how can I fix Honda CR-V's key fob not working issue?

    Learn how to diagnose and fix the key fob not working issue in Honda CR-V. Step-by-step guide with diagnostic procedures and repair instructions.

    Component:Electrical
    Symptoms
    • •Key fob buttons do not respond
    • •Vehicle does not unlock or lock remotely
    • +{count} more

Share this solution

Comments

Sign in to share your thoughts

Sign In

No comments yet

Be the first to share your thoughts

Back to Generation