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 is having trouble reading how much fuel is in the alternative fuel tank. It's like when your video game controller can't tell how many lives you have left.
The P01AF code is triggered when the vehicle's powertrain control module (PCM) detects a problem with the circuit that monitors the fuel level in the alternative fuel tank.
The P01AF code indicates an issue with the circuit that connects the alternative fuel tank level sensor to the vehicle's PCM. This could be due to electrical problems, sensor failure, or communication issues between components.
• Check Engine Light is on
• Inaccurate fuel gauge readings
• Possible fuel system performance issues
• Faulty fuel tank level sensor
• Wiring issues such as shorts or open circuits
• Corroded or damaged connectors
PCM: Powertrain Control Module, the vehicle's onboard computer that controls engine and transmission functions.
OBD-II: On-Board Diagnostics, a standardized system in vehicles for self-diagnosing and reporting.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors of the fuel tank level sensor.
• Test the fuel tank level sensor for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty fuel tank level sensor.
• Clear the code and test drive to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Chevrolet Volt
• Toyota Prius
• Nissan Leaf
• Regularly inspect fuel system wiring.
• Ensure connectors are clean and tight.
• Schedule periodic maintenance checks.
Sensor Issue
• Avoid running the vehicle on low fuel to prevent sensor damage.
• Get the issue diagnosed and repaired promptly to avoid further complications.
Check with your vehicle manufacturer as fuel system components may be covered under warranty.
This code has become more prevalent with the rise of hybrid and alternative fuel vehicles, as they often have additional fuel systems.
Moderate – While not immediately critical, it should be addressed to ensure accurate fuel readings and prevent potential fuel system issues.
Driving with a malfunctioning fuel level sensor can lead to unexpected fuel shortages and potential safety hazards.
• Vehicle must be running.
• Fuel tank should have a measurable amount of fuel.
The alternative fuel tank level sensor is typically located in or near the alternative fuel tank, often accessible from underneath the vehicle or through the trunk area.
Q: Can I drive with a P01AF code?
A: While you can drive with this code, it's best to get it fixed soon to avoid running out of fuel unexpectedly.
Q: How do I reset the P01AF code?
A: After repairs, you can reset the code using an OBD-II scanner. If the issue is fixed, the code should not return.
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