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 there is a problem with the sensor that checks how full the alternative fuel tank is. It's like when a game controller isn't working right and the game doesn't know what button you're pressing.
The P2A42 code indicates that the pressure sensor for the alternative fuel tank is not reading within the expected range, which can affect fuel management.
The P2A42 code is triggered when the Engine Control Module (ECM) detects a signal from the alternative fuel tank B pressure sensor that is outside the expected range. This could be due to a faulty sensor, wiring issues, or a problem with the fuel tank itself.
• Check Engine Light is on
• Erratic fuel gauge readings
• Possible fuel odor
• Faulty pressure sensor
• Wiring issues or poor connection
• Fuel tank pressure imbalance
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the pressure sensor.
• Test the pressure sensor for proper operation.
• Replace the faulty pressure sensor.
• Repair or replace damaged wiring.
• Ensure proper sealing of the fuel tank.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $400
Moderate
• Toyota Prius
• Honda Civic CNG
• Chevrolet Volt
• Regularly inspect fuel tank and sensor connections.
• Use quality fuel to prevent sensor contamination.
• Schedule periodic maintenance checks.
Sensor Issue
• Avoid driving with a full alternative fuel tank until repaired.
• Monitor fuel levels manually if possible.
• Seek professional assistance for diagnosis.
Check if the vehicle's warranty covers sensor issues.
This code has been more common in vehicles with alternative fuel systems as they age.
Moderate – It should be addressed soon to prevent fuel management issues.
Driving with unresolved fuel system issues can lead to increased emissions and potential safety hazards.
• Vehicle must be running.
• Alternative fuel system must be active.
The pressure sensor is typically located on or near the alternative fuel tank.
Q: Can I drive with a P2A42 code?
A: It's possible, but not recommended as it can lead to incorrect fuel readings and potential safety issues.
Q: How do I reset the P2A42 code?
A: After repairs, use an OBD-II scanner to clear the code from the vehicle's computer.
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