Error Code P2243: What It Means & What To Do?

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If you notice a lean or risk condition in the engine, decreased fuel efficiency, black smoke from the taillight, and/or illuminated Check Engine Light on the dashboard, them there is a major possibility that you are dealing with the OBD Code P2243 with your vehicle.

Possible causes may include a faulty oxygen sensor, faulty electrical connector at the oxygen sensor, faulty or shorted wiring in the oxygen sensor circuit, a blown fuse for the oxygen sensor (if applicable), low or excessive fuel pressure, a vacuum leak on the engine, excessive exhaust leaks, or a faulty PCM.

When an oxygen sensor for a particular engine bank delivers a voltage signal that is not within the accepted parameters, causing the PCM to store a trouble code and possibly illuminate the service engine soon light, it is typically a P2243 error code. Bank 1 typically denotes the engine bank of the engine block that does not contain the number 1 cylinder.

This code is seen when the Engine Control Module (ECM) tries to control the heater control circuit for Bank 1 Sensor 1 and finds high voltage present. The heater is an integral part of sensor function that is used to heat the oxygen sensor to operating temperature until the vehicle warms up. Oxygen sensors must be at operating temperature to provide accurate readings to the ECM for air fuel ratio control.

What causes this problem with the O2 Sensor Reference Voltage Circuit Open Bank 1 Sensor 1?

• Wiring of Heated Oxygen Sensor is open or short
• Electrical connections to the Oxygen Sensor are faulty
• Faulty or damaged Oxygen Sensor
• Circuit fuse of the sensor is blown
• ECM/PCM fault or failure
• Fuel Delivery Systems and Exhaust Systems Leakages

1. Engine Control Module - Dead cells in batteries can cause a failure in the engine control module. Many times a battery is left in the rig long after a cell has died. This would affect the grounding in the car battery.
2. Powertrain Control Module - If there are some faults in the PCM, then it may throw off the timing and fuel settings of the engine, which can negatively affect the performance. A flawed PCM may cause the vehicle to experience a reduction in fuel efficiency, power as well as acceleration.
3. Exhaust Gas Recirculation Valve - Bad EGR valve can cause many performance issues. Common signs include engine performance issues like decreased power and acceleration, rough idle, and the Check Engine Light coming on. Thus, replace faulty EGR valve now!
4. Diesel Exhaust Fluid Pump - If the DEF pump will not function properly, it can cause increased emissions in the exhaust system and reduced the longevity of the filtration elements in the exhaust system. Thus, replace faulty pump immediately.
5. Electronic Control Unit - Do you know that the poor performance or unexplained drops in fuel economy or efficiency are often associated to onboard car computer problems, or defective ECU issues?
6. Diagnostic Tools - Use factory grade diagnostic tools to resolve OBD code P2243 error. Buy new diagnostic tools and equipment for us.
7. Fluid Pump Control Module - If the control module is faulty, the pump will not be able to work properly and will not be able to transfer fluid to the transmission and hydraulic system efficiently. Thus, replacements are in order.
8. Engine Coolant Temperature Sensor - One major symptom of defective engine coolant temperature sensor is an overheating car engine. This can also cause engine misfiring. Take care of your car engine coolant temperature sensor and replace it if needed.
9. Catalytic Converter - Catalytic converters at fault will lead to dropped fuel efficiency and performance along with increased emissions. Thus replace faulty parts now!
10. Manifold Gasket Set - Check for faults in the intake gaskets as it will hamper the engine performance as well as the intake system and fuel delivery system as well. Thus, replace it now!
11. Air Filters - Check for clogged and damaged air filters and replace them immediately as it will hamper the air intake systems. Buy new filters now!
12. Mass Air Flow Sensor - A faulty mass airflow sensor will cause problems similar to low compression or low vacuum, and will also show symptoms similar to when your vehicle has low fuel pressure from a faulty fuel pump. Thus, replace damaged/faulty MAF sensor today!
13. Diesel Exhaust Fluid Pump - If the DEF pump will not function properly, it can cause increased emissions in the exhaust system and reduced the longevity of the filtration elements in the exhaust system. Thus, replace faulty pump immediately.
14. Heated Oxygen Sensor - A faulty sensor will not function properly and not analyse the air to fuel ratio in the exhaust. Visit us today to replace damaged oxygen sensors.

It is essential to know the symptoms of an issue as only then you would be able to solve the problem. So that’s why we have listed out some major symptoms of OBD Code P2243 here:

Common Symptoms

• Rich/Lean engine-running condition
• Decrease in fuel economy due to increased fuel consumption
• Loss of engine power and acceleration
• Rough idling and throttle response
• White or black smoke from the exhaust tailpipe
• Hard starting and stalling in some cases
• CHECK ENGINE light indication on 

Here are some ways with the help of which you will be able to correct the OBD Code P2243.

• Replacement of MAF (Mass Air Flow) sensor
• Air Intake Pipe replacement
• Intake Manifold Seal/valve replacement
• Wiring/connections to the MAF (Mass Air Flow) sensor to be replaced
• Oxygen sensor repair or replacement
• O2 sensor faulty wiring and connector replacement

There is no need to be anxious as Parts Avatar – Car Parts Online is here to help you out! We have high grade ECM, O2 Sensor, Sensor Connector and a lot more for our precious customers.

Here are some steps which you should follow in order to diagnose this fault code:

• The diagnosis starts with a complete visual inspection of the Bank 1, Sensor 1 of the sensor, as well as its wiring and harness.
• Check for bare wires, especially those entering the sensor. These wires can be stained and worn out and cause shorts. It is important that all wires are away from the exhaust. Also any damaged wires need to be replaced.
• The highest rate of failure for Code P2243 is of the oxygen sensor and it is quickest to check the resistance of the heater circuit first. Every manufacturer notifies the specified amount of resistance that each sensor should have. If the resistance measured falls out of the specified range, then the sensor is deemed to be faulty and is needed to be replaced.
• In the next step, the wiring for the sensor is checked and examined along with the harness for any signs of damage. Most probable cause of damage is usually debris on the road that gets under the car and damages the wiring.
• Other things that can damage the wiring is from rodents or harnesses being incorrectly routed during other repairs, causing the wires to rub through and get short out.
• Measure the resistance of the wiring running from the powertrain control module to the sensor and if the resistance is more than the limit, there is probably a problem with the circuit. At this point, the simplest solution is to replace the wire from end to end.
• After checking all of the above the final inspection come the point of checking the powertrain control module for faults and reprogram, if needed.

Common Mistakes When Diagnosing the P2243 Code

• Replacing the O2 Sensor without doing proper diagnosis and check for faults in other components
• It is also possible to overlook that the engine may be running too rich which is causing the exhaust gas mixture to be too rich causing the oxygen sensor to read high voltage
• Also check for faulty wiring and harness in association to the sensor and circuits