Engine-Codes.com
Engine-Codes – Honda – P0138 2000 Honda Civic

P0138 2000 Honda Civic Code - HO2S Bank 1 Sensor 2 Circuit Low Voltage

Quick Answer

The P0138 code for a 2000 Honda Civic specifically refers to the HO2S (Heated Oxygen Sensor) Bank 1 Sensor 2 Circuit Low Voltage. Common causes include Faulty oxygen sensor, Damaged wiring or connectors in the sensor circuit, Exhaust leaks near the oxygen sensor. 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
P0138 2000 Honda Civic indicates HO2S Bank 1 Sensor 2 Circuit Low Voltage.
Common causes
Common causes include Faulty oxygen sensor, Damaged wiring or connectors in the sensor circuit, Exhaust leaks near the oxygen sensor.
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.
What is this?
Table of contents Created and updated by William Orellana on Sep 13, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P0138 2000 Honda Civic Description

The P0138 code for a 2000 Honda Civic specifically refers to the HO2S (Heated Oxygen Sensor) Bank 1 Sensor 2 Circuit Low Voltage. This code indicates that the oxygen sensor located downstream of the catalytic converter on Bank 1 is sending a signal to the engine control module (ECM) that is lower than the expected voltage range. The oxygen sensor plays a crucial role in monitoring the oxygen levels in the exhaust gases, allowing the ECM to adjust the air-fuel mixture for optimal combustion.

OBDII Code P0138 2000 Honda Civic - HO2S Bank 1 Sensor 2 Circuit Low Voltage
P0138 2000 Honda Civic Code - HO2S Bank 1 Sensor 2 Circuit Low Voltage

Common Causes of P0138 2000 Honda Civic

  1. Faulty oxygen sensor
  2. Damaged wiring or connectors in the sensor circuit
  3. Exhaust leaks near the oxygen sensor
  4. Issues with the ECM
  5. Contaminated or poor-quality fuel affecting sensor readings

Symptoms of P0138 2000 Honda Civic

  1. Decreased fuel efficiency
  2. Rough idling or engine misfires
  3. Hesitation or lack of acceleration
  4. Illuminated check engine light
  5. Failed emissions test

How to Fix P0138 2000 Honda Civic

  1. Use an OBD-II scanner to confirm the P0138 code and identify the specific oxygen sensor causing the issue.
  2. Inspect the wiring and connectors in the sensor circuit for any damage or corrosion. Repair or replace as needed.
  3. Test the oxygen sensor's voltage output using a multimeter to determine if it is functioning correctly. Replace the sensor if readings are outside the specified range.
  4. Clear the code from the ECM's memory using the OBD-II scanner and perform a test drive to ensure the issue has been resolved.
  5. If the code persists, further diagnostics may be necessary to identify any underlying issues with the ECM or other components.

Cost to Fix P0138 2000 Honda Civic

The typical repair costs for addressing a P0138 code on a 2000 Honda Civic can range from $150 to $400, depending on the specific cause of the issue and the cost of parts and labor. This estimate includes the cost of a new oxygen sensor, potential wiring repairs, and diagnostic labor. It's important to note that prices can vary based on location, vehicle make and model, and the rates of individual auto repair shops. It's recommended to obtain quotes from multiple shops to ensure a competitive price for the repair.

What does this mean?

Tech Notes for P0138 2000 Honda Civic

Replacing the Rear Heated Oxygen Sensor Bank 1 usually takes care of the problem.

When is the Code Detected?

The P0138 code is set when the Engine Control Module (ECM) detects that the rear O2 sensor signal voltage remains excessively high for an extended period of time.

Need more information about the P0138 2000 Honda Civic code?

Need more information on how to fix the P0138 2000 Honda Civic code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0138 2000 Honda Civic 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 P0138 2000 Honda Civic Code

1. What does OBDII code P0138 mean for a 2000 Honda Civic?

- OBDII code P0138 indicates a problem with the HO2S (Heated Oxygen Sensor) Bank 1 Sensor 2 circuit, specifically low voltage.

2. What are common symptoms of OBDII code P0138 on a 2000 Honda Civic?

- Common symptoms include poor fuel economy, rough idling, hesitation during acceleration, and the illumination of the Check Engine Light.

3. What are possible causes of OBDII code P0138 on a 2000 Honda Civic?

- Possible causes include a faulty oxygen sensor, damaged wiring or connectors, exhaust leaks, a faulty catalytic converter, or issues with the engine's fuel system.

4. How can I diagnose OBDII code P0138 on a 2000 Honda Civic?

- Diagnose P0138 by using an OBDII scanner to retrieve the code, visually inspecting the oxygen sensor and its wiring, checking for exhaust leaks, and conducting voltage tests.

5. Can I drive my 2000 Honda Civic with OBDII code P0138?

- It is not recommended to drive your vehicle with a P0138 code, as it can lead to decreased fuel efficiency and potential damage to the catalytic converter over time.

6. How do I repair OBDII code P0138 on a 2000 Honda Civic?

- Repair options include replacing the oxygen sensor, repairing or replacing damaged wiring or connectors, fixing exhaust leaks, and addressing any issues with the fuel system.

7. Is it possible to reset OBDII code P0138 on a 2000 Honda Civic?

- You can reset the Check Engine Light and code temporarily, but it is important to address the underlying issue causing the P0138 code to prevent it from reoccurring.

8. How much does it cost to fix OBDII code P0138 on a 2000 Honda Civic?

- The cost of fixing P0138 can vary depending on the root cause, but it may range from $100 to $500 or more, including parts and labor.

9. Can a DIY enthusiast fix OBDII code P0138 on a 2000 Honda Civic?

- Depending on the skill level, a DIY enthusiast can potentially fix P0138 by replacing the oxygen sensor or addressing wiring issues, but professional diagnosis may be necessary for more complex problems.

10. How often does OBDII code P0138 occur in a 2000 Honda Civic?

- OBDII code P0138 can occur occasionally in a 2000 Honda Civic, especially as the vehicle ages and components like the oxygen sensor deteriorate. Regular maintenance and inspections can help prevent this code from appearing frequently.

Discuss the causes and fixes for P0138 2000 Honda Civic OBDII Code

Submit a New Comment

Code P0138 2000 Honda Civic comments

No comments found for this page.