What it means
A general electrical fault on barometric pressure sensor B — open, shorted, or out of plausibility. The sensor measures atmospheric pressure for altitude compensation; sensor B is a redundant or secondary unit.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Barometric Pressure Sensor B is a secondary or redundant sensor that reports atmospheric pressure for the engine control module's altitude compensation. P222A sets when the module detects a general circuit fault with Sensor B, such as an open, short, or implausible signal.
Common causes
Most likely first.
- Faulty barometric pressure sensor B
- Open, shorted, or damaged sensor wiring
- Corroded or loose connector
- Poor sensor power or ground
Symptoms
- Check-engine light on
- Reduced engine performance
- Increased fuel consumption
- Hesitation or rough running
How to diagnose it
- Record freeze-frame data and compare Sensor B's pressure reading with local conditions and Sensor A or other available pressure readings.
- Inspect the Sensor B connector and harness for corrosion, loose pins, damage, or a poor fit.
- Using vehicle wiring information, check Sensor B's power, ground, and signal circuits for opens or shorts.
- Check terminal contact and wiring continuity, then compare Sensor B's output with the manufacturer's specification.
- If the circuit is sound, test Barometric Pressure Sensor B according to the manufacturer's procedure.
Common fixes
- Reconnect Sensor B's loose connector or clean corroded terminals.
- Repair open, shorted, or damaged Sensor B wiring.
- Restore a poor Sensor B power or ground connection.
- Replace Barometric Pressure Sensor B if its output fails the manufacturer's test.
Can I keep driving?
Cautious driving is usually possible if the vehicle runs normally, but reduced performance, hesitation, or higher fuel use may occur. Avoid hard acceleration if engine response is poor and arrange diagnosis of the secondary pressure circuit.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.