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 when a toy with two batteries can't switch from one battery to the other.
The code indicates that there is an issue with the performance of the control circuit for the alternative fuel tank select valve C.
The P2A9A code is triggered when the Engine Control Module (ECM) detects a performance issue with the control circuit of the alternative fuel tank select valve C. This valve is responsible for switching between different fuel sources in vehicles that can use more than one type of fuel, such as gasoline and natural gas.
• Check Engine Light is on
• Vehicle may not switch between fuel tanks
• Reduced fuel efficiency
• Faulty alternative fuel tank select valve C
• Wiring issues in the control circuit
• Malfunctioning ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the alternative fuel tank select valve C for proper operation.
• Replace the faulty select valve C.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $500
Moderate
• Chevrolet Volt
• Toyota Prius
• Ford Fusion Hybrid
• Regularly inspect and maintain fuel system components.
• Ensure proper electrical connections.
• Use recommended fuel types.
Control Circuit Issue
• Avoid switching fuel types until the issue is resolved.
• Consult a professional mechanic if unsure about repairs.
Check with your vehicle manufacturer for warranty coverage on fuel system components.
This code is relatively uncommon and typically associated with vehicles that have alternative fuel systems.
Moderate – While the vehicle may still run, it is important to address the issue to ensure proper fuel system operation.
Operating a vehicle with a malfunctioning fuel system can lead to increased emissions and potential safety risks.
• Vehicle running on alternative fuel
• Switching between fuel tanks
The alternative fuel tank select valve C is typically located near the fuel tanks or along the fuel line.
Q: Can I drive with a P2A9A code?
A: You may be able to drive, but it's best to fix the issue soon to avoid potential problems.
Q: What fuel types are affected?
A: This code affects vehicles that use multiple fuel types, such as gasoline and natural gas.
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