2004 Toyota Camry P2238: All You Need To Know

For individuals who own a Toyota Camry, the 2004 Toyota Camry p2238 error code is not unusual, as code P0770 Toyota Corolla 2003,  especially if you drive your car frequently. The engine has broken down. If your car’s engine code is P2238, it signifies your machine has a problem that has to be fixed. There is no need to panic, but this problem needs to be solved.

What Is Code P2238 On A 2004 Toyota Camry? 

2004 Toyota Camry P2238

2004 Toyota Camry P2238 – Image source: Carparts

P2238 Toyota code is a diagnostic trouble code for O2 Sensors Positive Current Control Circuit Low Bank 1 Sensor 1. It indicates a problem with the circuitry that controls the engine’s voltage.

Any car built after 1996 has an engine control module with the general designation P2238. A mechanic must identify the underlying cause for this code to be set in your circumstances because it can occur for several reasons.

Your engine’s brain is known as the engine control module, which controls the air-fuel ratio, ensuring the safe operation of your car. You’ll need to replace the O2 sensor if the voltage that the ECM detects is outside of the normal range.

2004 Toyota Camry P2238: Common Causes

Bad Oxygen Sensor

O2 sensors measure the oxygen content of your exhaust emissions to determine engine efficiency. After 30,000 to 100,000 miles, oxygen sensors need to be replaced, and you should do this immediately. It’s only an issue of time before you begin to experience some concerning symptoms as your oxygen sensor malfunctions.

Bad O2 Sensor

Bad O2 Sensor 

The code P2238, check engine light turning on, poor fuel efficiency, and a rough idle indicate that a car’s oxygen sensor is malfunctioning. The engine’s system won’t be able to accurately establish the air-fuel ratio if an oxygen sensor malfunctions, which could lead to less efficient fuel use.

Burnt, Broken, Or Disconnected Wiring 

One explanation is corrosion in the O2 sensor’s wiring connector connectors or short circuits. A heater circuit problem is frequently the cause of an O2 sensor deficit.

Heater circuit

Heater circuit 

The internal failure of the O2 Sensor’s heater circuit is the most frequent cause of code P2238. If the cover is broken or removed, water may enter the Sensor’s backside, shorting out the heater circuit and damaging the relay or blowing the O2 sensor heater circuit fuse.

You must follow the O2 sensor’s wires. If you deleted the upper plenum, the space would feel more open. 

Faulty PCM 

The Powertrain Control Module was in charge of managing the engine’s many components and sensors. Data collection from various engine components and sensors is the PCM’s primary job.

Although the PCM is built to last a lifetime in your car, it may be problematic. The likelihood of the powertrain control module in your car failing is quite unlikely in the newest vehicle models. However, it could malfunction over time and result in code 2238.

Check engine light, decreased engine power, and shifting problems are a few indicators.

2004 Toyota Camry P2238: How To Fix

Check The Wire

You ought to inspect the wiring. Right behind the cylinder head on the passenger side, the wiring for the driver’s side connects to the harness. The O2 sensor must be unplugged. You must probe the sensor wires, use a multimeter, and set the multimeter to the resistant or continuity setting.

Next, insert one cable end into a cable on the O2 sensor plug, and then touch the other end to either the positive or negative battery cable. Once it beeps or when there is no resistance, you will know a wire has shorted; you then need to access the harness and fix the short.

Replace O2 Sensor

When the sensors are broken or malfunctioning, you should replace them. A bad O2 sensor won’t prevent you from running your vehicle, but replacing it as soon as possible is advisable.

O2 sensor

O2 sensor  

To start, identify the problematic sensor using an OBD scanner. If your engine has been running lately, let it cool before parking your car on a level surface.

The sensor should then be disconnected from the electrical connection and unscrewed using a torque wrench and an oxygen sensor socket. The replacement sensor must be installed and secured with a screw.

Replace The ECM

All of the vehicle’s sensors are communicated with by the ECM, which also receives and transmits signals. The ECM can malfunction and lead to code P2238 when the automobile is running. You ought to swap it out.

An ECM is a rectangular, silver module inside the engine chamber or elsewhere.

After removing them due to sustained ECM, use the socket wrench to reinstall the screws. Connect the battery, plug the electrical cables into the ECM, and turn the key to start the car.

The vehicle ID and information about the ignition key are typically stored in the ECM in cars with theft deterrent systems. Then, thoroughly inspect it before replacing it.


How Much To Replace Oxygen Sensor Toyota Camry?

O2 sensors in older automobiles typically survive 30,000–50,000 miles or 3–5 years. Replace the oxygen sensor in your car if you’ve over this limit. O2 sensors should be replaced at high mileage to ensure top performance and fuel efficiency.

Replacement oxygen sensors for Toyota Camrys typically cost from $372 and $429. $66 and $84 are the expected labor cost range.

Can I Replace An O2 Sensor Myself?

If you read the manufacturer’s instructions, you can replace an oxygen sensor yourself in most cars, which is convenient if you’re trying to save some money. There are only so many tools needed.

Ensure that the OEM parts you buy from your neighborhood auto parts store are compatible with your car.

However, a damaged O2 sensor cannot be fixed. Due to the materials and technology in its housing, it has to be replaced; replacing it will take much less time than if you were to do it yourself.

Can I Drive With A Faulty Oxygen Sensor?

The answer is that you can run with a bad oxygen sensor. Your automobile won’t stall out on you right away if your oxygen sensor malfunctions. But you should alter it right away since many car owners also have problems with P2238 Toyota Camry 2003, which was caused by a faulty O2 Sensor.

As the engine isn’t operating on the proper fuel mixture, we advise against driving with a malfunctioning oxygen sensor. Engine misfires, sluggish acceleration, rough idling, and a lit check engine light are all possible symptoms.


After reading this article, you should now be able to identify and resolve the 2004 Toyota Camry P2238. Before having your car repaired or replaced, it’s crucial to determine the problem.

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