AutoCodes – Toyota – P2239 2002 Toyota Highlander

P2239 2002 Toyota Highlander Code - A/F Sensor Bank 1 Short Circuit

Quick Answer

The Air-Fuel ratio (A/F) sensor provides output voltage approximately equal to the existing air-fuel ratio. Common causes include Faulty EFI Relay, Faulty Air/Fuel Sensor Bank 1, Air/Fuel Sensor Bank 1 harness is open or shorted. 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: P2239 2002 Toyota Highlander indicates A/F Sensor Bank 1 Short Circuit.
Common causes: Common causes include Faulty EFI Relay, Faulty Air/Fuel Sensor Bank 1, Air/Fuel Sensor Bank 1 harness is open or shorted.
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 4,505

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
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P2239 2002 Toyota Highlander Description

The Air-Fuel ratio (A/F) sensor provides output voltage approximately equal to the existing air-fuel ratio.
The A/F sensor output voltage is used to provide feedback for the Engine Control Module (ECM) to control the air-fuel ratio.
With the A/F sensor output, the ECM can determine deviation from the stoichiometric air-fuel ratio and control proper injection time. If the A/F sensor is malfunctioning, the ECM is unable to accurately control air-fuel ratio.
The A/F sensor is equipped with a heater which heats the zirconia element. The heater is also controlled by the ECM. When the intake air volume is low (the temperature of the exhaust gas is low), current flows to the heater which heats the sensor to facilitate detection of accurate oxygen concentration.
The A/F sensor is a planar type. Compared to a conventional type, the sensor and heater portions are narrower. Because the heat of the heater is conducted through the alumina to zirconia (of the sensor portion), sensor activation is accelerated.

The code is output when there is an open or short in the A/F sensor circuit, or if A/F sensor output drops. To detect these problems, the voltage of the A/F sensor is monitored when turning the ignition switch to the ON position, and the admittance (admittance is an electrical term that indicates the ease of flow of current) is checked while driving. If the voltage of the A/F sensor is between 0.6 V and 4.5 V, it is considered normal. If the voltage is outside of the specified range, or the admittance is less than the standard value, the ECM will determine that there is a malfunction in the A/F sensor. If the same malfunction is detected in the next driving cycle, the MIL is illuminated and a DTC is set.

OBDII Code P2239 2002 Toyota Highlander - A/F Sensor Bank 1 Short Circuit - AutoCodes.com — P2239 2002 Toyota Highlander Code - A/F Sensor Bank 1 Short Circuit

What does this mean?

What are the Possible Causes of the DTC P2239 2002 Toyota Highlander?

Faulty EFI Relay
Faulty Air/Fuel Sensor Bank 1
Air/Fuel Sensor Bank 1 harness is open or shorted
Air/Fuel Sensor Bank 1 circuit poor electrical connection
Faulty Engine Control Module (ECM)

How to Fix the DTC P2239 2002 Toyota Highlander?

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 P2239 2002 Toyota Highlander 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 P2239 2002 Toyota Highlander code?

Need more information on how to fix the P2239 2002 Toyota Highlander code? Get Access to Factory Service Manuals

Need Help with the Code?

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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 P2239 2002 Toyota Highlander Code

1. What are the common symptoms of OBDII code P2239 in a 2002 Toyota Highlander?

- Common symptoms include poor fuel economy, rough idling, engine misfires, and the illumination of the check engine light.

2. What does the OBDII code P2239 "A/F Sensor Bank 1 Short Circuit" indicate in a 2002 Toyota Highlander?

- This code indicates that there is a short circuit in the Air/Fuel (A/F) sensor in Bank 1 of the engine.

3. What are some possible causes of the A/F Sensor Bank 1 Short Circuit code in a 2002 Toyota Highlander?

- Potential causes include damaged wiring or connectors, a faulty A/F sensor, a blown fuse, or issues with the engine's computer.

4. How can I diagnose the A/F Sensor Bank 1 Short Circuit issue in my 2002 Toyota Highlander?

- Diagnosing this problem typically involves inspecting the A/F sensor and its wiring, checking for continuity, and testing the sensor's voltage output.

5. Can I continue driving my 2002 Toyota Highlander with the P2239 code present?

- It is recommended to address this issue promptly to prevent potential damage to the engine and ensure optimal fuel efficiency.

6. How can I repair the A/F Sensor Bank 1 Short Circuit problem in my 2002 Toyota Highlander?

- Repair options may include replacing the A/F sensor, repairing damaged wiring, replacing fuses, or resetting the engine's computer after fixing the issue.

7. Will resetting the check engine light resolve the P2239 code in a 2002 Toyota Highlander?

- Resetting the check engine light may temporarily turn it off, but the underlying issue causing the code will persist until properly diagnosed and repaired.

8. Are there any DIY tips for addressing the A/F Sensor Bank 1 Short Circuit in a 2002 Toyota Highlander?

- DIY enthusiasts with automotive experience may attempt to inspect wiring connections, replace the A/F sensor, or check fuses before seeking professional help.

9. How much can I expect to pay for repairs related to the P2239 code in a 2002 Toyota Highlander?

- The cost of repairs can vary depending on the specific issue, but it's advisable to budget for sensor replacement, wiring repairs, and potential diagnostic fees.

10. Can the A/F Sensor Bank 1 Short Circuit issue affect the overall performance of my 2002 Toyota Highlander?

- Yes, this issue can impact the engine's performance, fuel efficiency, and emissions, so it's essential to address it promptly to maintain the vehicle's optimal operation.