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 part of the car that switches between different fuel tanks. It's like if you had two cups to drink from, but the switch to choose which cup to drink from isn't working.
The P2A91 code indicates that the control circuit for the alternative fuel tank select valve is open or not functioning properly.
The alternative fuel tank select valve is responsible for switching between different fuel tanks in vehicles that use alternative fuels. An open circuit in this valve's control circuit means that the electrical signal needed to operate the valve is not being transmitted, possibly due to a broken wire or a faulty connection.
• Check Engine Light illuminated
• Inability to switch between fuel tanks
• Possible fuel delivery issues
• Faulty alternative fuel tank select valve
• Broken or damaged wiring in the control circuit
• Poor electrical connection in the circuit
Alternative Fuel: Fuel other than traditional gasoline or diesel, such as ethanol or natural gas.
Circuit: A complete path that allows electricity to flow.
• Perform a visual inspection of the wiring and connections to the select valve.
• Use a multimeter to check for continuity in the circuit.
• Test the select valve for proper operation.
• Repair or replace damaged wiring.
• Ensure all electrical connections are secure.
• Replace the alternative fuel tank select valve if faulty.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Toyota Prius
• Chevrolet Volt
• Honda Civic Hybrid
• Regularly inspect wiring for damage.
• Ensure connectors are clean and secure.
• Follow manufacturer maintenance schedules.
Electrical Circuit Issue
• Avoid using alternative fuel tanks until the issue is resolved.
• Consult a professional mechanic for diagnosis and repair.
Check with your vehicle manufacturer; this issue may be covered under powertrain or emissions warranty.
This code is more common in vehicles with dual fuel systems or alternative fuel capabilities.
Moderate – While the vehicle may still operate, fuel switching capabilities are compromised.
Operating a vehicle with this issue may result in fuel delivery problems, potentially leading to engine performance issues.
• Vehicle must be running.
• Attempt to switch between fuel tanks.
Typically located near the fuel tanks or along the fuel lines, depending on vehicle design.
Q: Can I drive my car with this code?
A: Yes, but you may not be able to switch between fuel tanks, which could affect fuel availability.
Q: Will this code affect my car's performance?
A: It might, especially if the car relies on switching between fuel tanks for optimal performance.
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