Technical Description of OBD-II Trouble Code
High Barometric Pressure Sensor B
What does that signify?
This is a generic diagnostic trouble code (DTC) for powertrain issues and is commonly found in 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 specific 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.
Additionally, these systems use fewer sensors to achieve similar results in terms of fuel management and efficiency. Barometric Air Pressure (BAP) sensors are typically 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 an OBD2 fault code includes a letter (such as “B”), it often indicates a specific aspect of the system being addressed, such as different banks, sensors, circuits, connectors, etc. In this case, the letter “B” helps identify the specific sensor being referred to. Multiple barometric sensors are often used to ensure accurate readings and facilitate fuel management. These sensors also help identify faults within the sensors or circuits. Consult your service manual for precise details regarding letter specifications for your particular vehicle.
The ECM sets the P222D code when it detects a high electrical value/reading in the Barometric pressure (BAP) “B” sensor or its circuit(s).
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 potential 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 lead to expensive internal engine damage in the future.
What are some of the symptoms of the code?
Symptoms associated with a P222D trouble code may include:
What are some of the common causes of the code?
Possible causes for the P222D code include:
What are some P222D troubleshooting steps?
Basic Step #1
Locate the Barometric Air Pressure (BAP) sensor in your specific vehicle. The sensor’s location can vary significantly, so it is crucial to find the correct sensor. Once located, inspect the BAP sensor for any physical damage. Consider the sensor’s surroundings, 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 for any obstructions that may be affecting the sensor. Obstructions can lead to false atmospheric pressure readings, which are crucial for optimal engine performance in fuel management systems.
Basic Step #4
Using a multimeter and referring to the desired electrical values for the barometric air pressure sensor, disconnect the connector from the sensor to access the pins. Follow manufacturer-specific diagnostic procedures with the desired values and compare them. Any values outside the specified range indicate a defective sensor. Replace the sensor following proper removal and installation procedures.
