What it means
Barometric sensor B below lower plausibility — short to ground. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
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 altitude compensation. P222C sets when its signal falls below the valid range, commonly because the signal wire is shorted to ground or its connection has excessive resistance.
Common causes
Most likely first.
- Short to ground
- Connector pins corroded - high contact resistance
- Harness chafing through insulation
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, water ingress, or insulation rubbed through to ground.
- Using vehicle wiring information, check the Sensor B signal line for a short to ground and inspect its power and ground connections.
- Check connector pin fit and circuit continuity while gently moving the harness to expose an intermittent low signal.
- If the circuit is sound, test Barometric Pressure Sensor B against the manufacturer's diagnostic procedure.
Common fixes
- Clean and secure corroded or loose Sensor B connector pins.
- Repair the Sensor B signal wire shorted to ground or chafed through its insulation.
- Replace a damaged terminal or connector that creates excessive contact resistance.
- Replace Barometric Pressure Sensor B if its output remains below range with verified wiring.
Can I keep driving?
Cautious driving is generally possible if the engine runs normally, but reduced performance, hesitation, or higher fuel use may occur. Avoid hard acceleration if it responds poorly and arrange diagnosis of the Sensor B 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.