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 the car's computer thinks the air pressure sensor is reading too low after the engine is turned off. It's like if your weather app said the air pressure outside is way too low, which might mean the sensor is not working right.
The barometric pressure sensor measures the atmospheric pressure. This code indicates that the sensor is reading a pressure that is too low after the engine has been turned off.
P122A is triggered when the Engine Control Module (ECM) detects that the barometric pressure sensor 'B' is reading a pressure lower than expected during the afterrunning diagnosis. This could be due to a malfunctioning sensor or an issue with the sensor's circuit.
• Check Engine Light is on
• Poor engine performance
• Possible issues with fuel efficiency
• Faulty barometric pressure sensor
• Wiring issues in the sensor circuit
• Faulty ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the barometric pressure sensor.
• Test the barometric pressure sensor using 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
• Regular maintenance checks
• Ensure sensor connections are secure
• Avoid exposure to harsh environmental conditions
Sensor Issue
• Have the vehicle inspected by a professional.
• Do not ignore the Check Engine Light.
Check with the vehicle manufacturer for warranty coverage on sensors.
This code has been associated with sensor failures in certain models, leading to recalls or technical service bulletins in the past.
Moderate – It should be addressed to prevent further engine performance issues.
Driving with a faulty sensor can lead to increased emissions and potential engine damage.
• Engine off
• Stable atmospheric conditions
The barometric pressure sensor is typically located near the intake manifold or integrated into the ECM.
Q: Can I drive with a P122A code?
A: It's not recommended to drive for extended periods with this code as it can affect engine performance.
Q: How can I reset the Check Engine Light after fixing the issue?
A: Use an OBD-II scanner to clear the code after the repair.
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