Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is getting a signal that the sensor measuring the fuel level in the alternative fuel tank is too low. It's like when your game controller says the battery is low, but for the fuel tank.
This code indicates that the signal from the alternative fuel tank level sensor is below the expected range.
The P01B1 code is triggered when the Powertrain Control Module (PCM) detects a voltage signal from the alternative fuel tank level sensor that is lower than the specified range. This sensor is responsible for providing the PCM with the current level of fuel in the alternative fuel tank. A low circuit signal can indicate a fault in the sensor, wiring, or connections.
• Check Engine Light is on
• Inaccurate fuel gauge reading
• Potential fuel delivery issues
• Faulty alternative fuel tank level sensor
• Wiring issues such as shorts or open circuits
• Poor electrical connections
• Faulty PCM
PCM: Powertrain 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 fuel tank level sensor.
• Test the sensor for proper operation.
• Check the PCM for any faults.
• Repair or replace faulty wiring or connectors.
• Replace the alternative fuel tank level sensor if defective.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $500
Moderate
• Chevrolet Volt
• Toyota Prius
• Ford Fusion Hybrid
• Regularly inspect wiring and connections for damage.
• Ensure proper maintenance of the fuel system.
• Use quality fuel to prevent sensor contamination.
Sensor Issue
• Have the vehicle inspected by a professional if the Check Engine Light is on.
• Avoid running the vehicle on low fuel levels to prevent sensor issues.
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
This code is relatively uncommon and typically associated with vehicles using alternative fuels.
Moderate – It should be addressed to ensure accurate fuel level readings and prevent potential fuel delivery issues.
Driving with a faulty fuel level sensor can lead to unexpected fuel shortages, which may be hazardous.
• Vehicle must be running.
• Fuel level sensor circuit must be active.
The alternative fuel tank level sensor is typically located inside the alternative fuel tank.
Q: Can I drive with a P01B1 code?
A: It's possible, but not recommended as it may lead to inaccurate fuel level readings.
Q: How can I reset the Check Engine Light?
A: After repairs, use an OBD-II scanner to clear the code and reset the light.
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