AutoCodes – Jaguar – P0138 Jaguar

P0138 Jaguar Code - O2 Sensor Circuit High Voltage Bank 1 Sensor 2

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 Rear Heated Oxygen Sensor Bank 1, Rear Heated Oxygen Sensor Bank 1 harness is open or shorted, Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection. 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 Jaguar indicates O2 Sensor Circuit High Voltage Bank 1 Sensor 2.
Common causes: Common causes include Faulty Rear Heated Oxygen Sensor Bank 1, Rear Heated Oxygen Sensor Bank 1 harness is open or shorted, Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection.
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.

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Code Popularity 11,550

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 Jun 14, 2020

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0138 Jaguar 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 P0138 Jaguar - O2 Sensor Circuit High Voltage Bank 1 Sensor 2 - AutoCodes.com — P0138 Jaguar Code - O2 Sensor Circuit High Voltage Bank 1 Sensor 2

What does this mean?

What are the Possible Causes of the DTC P0138 Jaguar?

Faulty Rear Heated Oxygen Sensor Bank 1
Rear Heated Oxygen Sensor Bank 1 harness is open or shorted
Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection
Intake air leaks
Exhaust gas leaks
Inappropriate fuel pressure
Faulty fuel injectors

How to Fix the DTC P0138 Jaguar?

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

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

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0138 Jaguar 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.

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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 P0138 Jaguar Code

1. What are the common symptoms of OBDII code P0138 in a Jaguar?

- Common symptoms include decreased fuel efficiency, rough idling, stalling, and an illuminated check engine light.

2. What does the OBDII code P0138 Jaguar indicate?

- The code P0138 indicates a high voltage condition in the O2 sensor circuit of Bank 1 Sensor 2 in your Jaguar.

3. What are some possible causes of OBDII code P0138 in a Jaguar?

- Possible causes include a faulty O2 sensor, wiring issues, exhaust leaks, engine misfires, or a malfunctioning catalytic converter.

4. How can I diagnose the OBDII code P0138 in my Jaguar?

- Diagnosing P0138 involves using an OBDII scanner to retrieve the code, inspecting the O2 sensor and its wiring, checking for exhaust leaks, and testing the catalytic converter.

5. Can I still drive my Jaguar with the OBDII code P0138 present?

- It is not recommended to drive your Jaguar with the P0138 code present, as it can lead to further engine damage and poor performance.

6. How can I repair the O2 sensor circuit high voltage issue in my Jaguar?

- Repair options include replacing the faulty O2 sensor, repairing damaged wiring, fixing exhaust leaks, addressing engine misfires, or replacing a malfunctioning catalytic converter.

7. Will resetting the check engine light make the OBDII code P0138 go away?

- Resetting the check engine light will not fix the underlying issue causing the P0138 code. It is important to diagnose and repair the problem to prevent further damage.

8. What are some tips for preventing OBDII code P0138 in a Jaguar?

- Regular maintenance, such as timely O2 sensor replacement, checking for exhaust leaks, and addressing engine issues promptly, can help prevent the occurrence of code P0138.

9. Can a DIY enthusiast fix the OBDII code P0138 issue in a Jaguar?

- Depending on your skill level and access to tools, some DIY enthusiasts may be able to address the P0138 code by replacing the O2 sensor or fixing wiring issues.

10. How much does it cost to repair OBDII code P0138 in a Jaguar?

- The cost of repairing P0138 can vary depending on the exact cause of the issue. Costs may include parts and labor for O2 sensor replacement, wiring repairs, or catalytic converter replacement.