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 saying that the sensor that tells how much fuel is in the alternative fuel tank is showing a number that's too high.
The P01B2 code is triggered when the vehicle's powertrain control module (PCM) detects a high voltage signal from the alternative fuel tank level sensor circuit, indicating a possible issue with the sensor or wiring.
The alternative fuel tank level sensor measures the amount of fuel in the tank and sends this information to the PCM. A 'circuit high' condition means the voltage reading is higher than the expected range, which could indicate a short circuit, faulty sensor, or wiring issue.
• Check engine light is on
• Inaccurate fuel gauge reading
• Possible fuel system performance issues
• Faulty fuel tank level sensor
• Short circuit in the sensor wiring
• Poor electrical connection
• Faulty PCM
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, second generation
• Scan for additional codes and freeze frame data.
• Inspect the sensor and wiring for damage.
• Test the sensor's voltage and resistance.
• Replace the faulty fuel tank level sensor.
• Repair or replace damaged wiring.
• Ensure all electrical connections are secure.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Chevrolet Volt
• Toyota Prius
• Nissan Leaf
• Regularly inspect the fuel system wiring.
• Keep the fuel tank clean and free of debris.
• Ensure proper maintenance of the vehicle's electrical system.
Sensor Issue
• Do not ignore the check engine light.
• Have the vehicle inspected by a professional if unsure.
• Monitor fuel gauge readings for irregularities.
Check with the vehicle manufacturer for specific warranty coverage on fuel system components.
This code is more common in vehicles with alternative fuel systems, such as hybrids and electric vehicles.
Moderate – While the vehicle may still operate, it's important to address this issue to ensure accurate fuel readings and prevent further damage.
Driving with a malfunctioning fuel level sensor can lead to unexpected fuel shortages, which may be hazardous.
• Vehicle at operating temperature
• Fuel system pressurized
The alternative fuel tank level sensor is typically located inside the fuel tank or mounted on the fuel tank assembly.
Q: Can I drive with a P01B2 code?
A: It's possible to drive, but it's not recommended as it may lead to inaccurate fuel readings and potential fuel system issues.
Q: How do I reset the check engine light after fixing the issue?
A: Use an OBD-II scanner to clear the codes after the repair is completed.
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