Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the sensor that checks the temperature of the alternative fuel tank in your car. It's like when your thermometer at home doesn't work right and can't tell you the correct temperature.
The P01AA code is triggered when the vehicle's engine control module (ECM) detects an issue with the circuit of the alternative fuel tank temperature sensor.
The alternative fuel tank temperature sensor monitors the temperature of the fuel in vehicles that use alternative fuels, such as natural gas or propane. This sensor sends data to the ECM to help manage fuel efficiency and emissions. A fault in this circuit can lead to incorrect temperature readings, affecting engine performance.
• Check Engine Light illuminated
• Poor fuel efficiency
• Erratic engine performance
• Faulty alternative fuel tank temperature sensor
• Damaged or corroded wiring/connectors
• ECM malfunction
ECM: Engine Control Module, the computer that controls engine functions.
OBD-II: On-Board Diagnostics, a standardized system for self-diagnosing vehicle issues.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the sensor for proper operation.
• Replace the faulty temperature sensor.
• Repair or replace damaged wiring/connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$100 - $300
Moderate
• Chevrolet Volt
• Toyota Prius
• Ford Fusion Hybrid
• Regularly inspect wiring and connectors.
• Ensure proper maintenance of the fuel system.
• Use high-quality fuel to prevent sensor contamination.
Sensor Issue
• Have the vehicle inspected by a professional if the Check Engine Light is on.
• Avoid driving long distances until the issue is resolved to prevent further damage.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
This code is more common in vehicles that have been converted to use alternative fuels.
Moderate – It is advisable to address this issue soon to avoid potential engine performance problems.
Ignoring this code can lead to increased emissions and potential legal issues with emissions testing.
• Engine running
• Alternative fuel tank filled
The alternative fuel tank temperature sensor is typically located near the alternative fuel tank, often under the vehicle.
Q: Can I drive with a P01AA code?
A: While you can drive with this code, it is not recommended as it may affect fuel efficiency and emissions.
Q: How do I reset the Check Engine Light after fixing the issue?
A: You can use an OBD-II scanner to clear the code, or the light may turn off automatically after several drive cycles if the issue is resolved.
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