Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that a sensor in your car is detecting that the air pressure is too high, even after the engine is turned off.
The P122B code is triggered when the Engine Control Module (ECM) detects that the barometric pressure sensor 'B' is reading a pressure that is too high during the afterrunning diagnosis phase.
The barometric pressure sensor 'B' is responsible for measuring atmospheric pressure. This information is used by the ECM to adjust engine parameters for optimal performance. If the sensor reads a pressure that is too high after the engine has been turned off, it may indicate a fault in the sensor or a related component.
• Check Engine Light is on
• Poor engine performance
• Inconsistent fuel economy
• Faulty barometric pressure sensor
• Wiring issues or poor electrical connections
• Faulty ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the barometric pressure sensor and its wiring for damage.
• Test the sensor's output with a multimeter.
• Replace the barometric pressure sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regularly inspect and maintain sensors.
• Ensure electrical connections are secure.
• Keep the ECM updated with the latest software.
Sensor Issue
• Have a professional diagnose the issue if you're unsure.
• Do not ignore the Check Engine Light.
Check with your vehicle manufacturer for warranty coverage related to sensors.
This code has been associated with vehicles that have advanced engine management systems.
Moderate – Address the issue to prevent potential engine performance problems.
Driving with a faulty sensor can lead to increased emissions and reduced fuel efficiency.
• Engine off
• Stable atmospheric conditions
The barometric pressure sensor is typically located near the intake manifold or within the ECM housing.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to poor engine performance and increased fuel consumption.
Q: Can I drive my car with this code?
A: While the car may still be drivable, it's best to address the issue to avoid further problems.
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