Technical Description of OBD-II Trouble Code
Correlation between Barometric Pressure Sensor A and B
What does that signify?
This is a generic diagnostic trouble code (DTC) that applies to OBD-II vehicles. It can affect various vehicle brands such as Chevy, Mazda, Volvo, Acura, Honda, BMW, Isuzu, Mercedes Benz, Cadillac, Hyundai, Saab, Ford, GMC, etc. The repair steps may vary depending on the year, make, model, and powertrain configuration of the vehicle.
Most Engine Control Modules (ECMs) rely on multiple measurements to maintain an optimal air to fuel ratio for the engine. The ideal air/fuel ratio is known as the “stoichiometric” mixture, which is 14.7 parts air to one part fuel. The ECM monitors various values such as air flow, coolant temperature, engine speed, load demand, atmospheric temperature, etc., to keep the fuel mixture as close to stoichiometric as possible. Some engine management systems prioritize intake and atmospheric pressures to optimize the mixture.
In some cases, Barometric Air Pressure (BAP) sensors are used alongside Manifold Absolute Pressure (MAP) sensors. BAP sensors measure atmospheric pressure, which is crucial for determining fuel mixtures. The ECM compares atmospheric pressures to intake manifold pressures to accurately adjust the fuel mixture based on the driver’s needs. Altitude plays a significant role in diagnosing BAPs, as symptoms may worsen or improve depending on the location, especially in mountainous areas.
When a letter is included in the description of an OBD2 fault code, it usually indicates a specific aspect of the system being addressed, such as different banks, sensors, circuits, connectors, etc. In this case, it helps determine which sensor is being referred to. Multiple barometric sensors are often used to ensure accurate readings and assist in fuel management. Additionally, they help identify faults within the sensors or circuits. Consult your service manual for specific details regarding letter specifications for your vehicle.
The ECM sets the P222F code when it detects a variance in the signals from Barometric Pressure (BAP) sensor or its circuit(s) “A” and “B”.
A barometric pressure sensor:
What is the severity of this DTC?
The severity of this DTC is moderately high. It is important to address this issue promptly to ensure efficient engine operation. If a fault can directly impact critical values like air/fuel ratios and is actively present, it is advisable not to operate the vehicle to prevent engine damage. However, if you have driven the vehicle since the fault occurred, there may not be immediate cause for concern. Nevertheless, if left unattended, this fault could potentially lead to expensive internal engine damage in the future.
What are some of the symptoms of the code?
Symptoms of a P222F trouble code may include:
What are some of the common causes of the code?
Possible causes for the P222F code include:
What are some P222F troubleshooting steps?
Basic Step #1
Locate the Barometric Air Pressure (BAP) sensor on your specific vehicle. The sensor’s location can vary significantly, so it is crucial to find the correct sensor. Inspect the BAP sensor for any physical damage, considering factors such as high heat areas, engine vibrations, exposure to elements/road debris, etc.
Basic Step #2
Ensure that the connector on the sensor is properly seated to establish a good electrical connection. If the sensor is located on the engine, vibrations may cause connections to loosen or become physically damaged.
NOTE: Remember to disconnect the battery before disconnecting any sensors to avoid damaging electrical spikes. If you are uncomfortable with this step or have limited electrical knowledge, it is recommended to have your vehicle towed/driven to a reputable repair facility.
Basic Step #3
Check if there is anything obstructing the sensor, as it could lead to false atmospheric pressure readings. Accurate readings are crucial for optimal engine performance in fuel management systems.
Basic Step #4
Using a multimeter, follow the manufacturer’s specific diagnostic procedures and desired electrical values for the barometric air pressure sensor. Disconnect the connector from the sensor to access the pins. Compare the measured values with the specified range. Any values outside the range indicate a defective sensor, which should be replaced following proper removal and installation procedures.
