Barometric Pressure Sensor A Circuit Low
What does P2228 mean?
The P2228 code means the vehicle's onboard diagnostic system has detected: Barometric Pressure Sensor A Circuit Low. This is a low severity code.
Common Symptoms
- Check Engine Light on
- Lean running condition
- Decreased performance at lower altitudes
- Poor fuel economy
- Slight hesitation on acceleration
Probable Causes (Ranked by Likelihood)
- Open circuit in the BARO sensor A wiring Very High
- Failed barometric pressure sensor A High
- Corroded sensor A connector Moderate
- Sensor reference voltage supply issue Moderate
- ECM internal fault on sensor A input Low
Step-by-Step Diagnostic Procedure
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Read BARO sensor A value with a scan tool and compare to actual atmospheric pressure
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Check for 5V reference voltage at the sensor connector
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Inspect wiring from sensor A to the ECM for open circuits
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Test the sensor ground circuit for continuity
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Replace the sensor if wiring and voltage supply are confirmed good
Frequently Asked Questions
What is the difference between BARO sensor A and B?
Some vehicles use dual barometric pressure sensors (A and B) for redundancy or for different measurement ranges. Sensor A and B codes refer to specific sensor circuits within the system.
What voltage should the BARO sensor reference be?
Most BARO sensors use a 5V reference voltage from the ECM. If this reference is missing or low, the sensor cannot produce an accurate reading.
Can a low BARO reading cause the engine to run lean?
Yes, a low barometric pressure reading tells the ECM the vehicle is at a higher altitude than it actually is, causing it to reduce fuel delivery and potentially creating a lean running condition.