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 pressure sensor in the third alternative fuel tank is reading too high. It's like a balloon that's filled with too much air.
The P2A49 code is triggered when the vehicle's powertrain control module (PCM) detects a high voltage signal from the pressure sensor in the alternative fuel tank C, indicating that the pressure is higher than expected.
The alternative fuel tank C pressure sensor monitors the pressure within the tank to ensure it is within safe operating limits. A high circuit signal indicates an issue with the sensor or the wiring, which could result in inaccurate pressure readings and potential safety concerns.
• Check Engine Light is on
• Possible fuel smell
• Reduced fuel efficiency
• Faulty pressure sensor
• Wiring issues such as shorts or open circuits
• Faulty PCM
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the pressure sensor with a multimeter.
• Replace the pressure sensor if faulty.
• Repair or replace damaged wiring.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $400
Moderate
• Chevrolet Volt
• Toyota Prius
• Honda Civic Natural Gas
• Regular maintenance checks
• Ensure proper wiring connections
• Use quality fuel
Sensor Issue
• Get the vehicle checked by a professional.
• Avoid driving if there's a strong fuel smell.
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
This code has been more prevalent in vehicles using alternative fuels due to the complexity of additional fuel systems.
Moderate – Should be addressed to prevent potential safety issues.
Driving with a malfunctioning fuel system can be dangerous and may violate emissions regulations.
• Vehicle must be running
• Fuel tank should be pressurized
The pressure sensor is located on or near the alternative fuel tank C, typically underneath the vehicle.
Q: Can I drive with this code?
A: It's not recommended to drive for long periods with this code due to potential safety risks.
Q: Will this affect my fuel efficiency?
A: Yes, a faulty pressure sensor can lead to reduced fuel efficiency.
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