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 a part in the car that controls the flow of alternative fuel is not working properly. It's like a valve that should open and close, but it's stuck closed.
The P2A27 code indicates an issue with the control circuit for the alternative fuel tank shutoff valve, which is not performing as expected or is stuck in the off position.
The P2A27 code is triggered when the Powertrain Control Module (PCM) detects that the alternative fuel tank shutoff valve C is not operating correctly. This valve is responsible for controlling the flow of alternative fuel, and a malfunction can lead to improper fuel management.
• Check Engine Light is on
• Reduced fuel efficiency
• Difficulty in switching fuel types
• Faulty shutoff valve
• Wiring issues in the control circuit
• PCM malfunction
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Inspect the shutoff valve for physical damage.
• Check the wiring and connectors for the control circuit.
• Test the PCM for any faults.
• Replace the faulty shutoff valve.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $500
Moderate
• Toyota Prius
• Honda Civic Hybrid
• Chevrolet Volt
• Regular maintenance of fuel systems
• Periodic inspection of wiring and connectors
• Use high-quality alternative fuels
Control Circuit Issue
• Avoid switching fuel types until repaired.
• Consult a professional mechanic for diagnosis.
• Monitor fuel efficiency for any changes.
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
This code has been associated with vehicles using alternative fuels, often appearing in models with hybrid or dual-fuel systems.
Moderate – It should be addressed soon to prevent fuel management issues.
Driving with this code may affect emissions and fuel efficiency, potentially leading to legal issues in areas with strict emissions regulations.
• Engine at operating temperature
• Alternative fuel system engaged
The alternative fuel tank shutoff valve is typically located near the fuel tank or along the fuel line.
Q: Can I drive my car with a P2A27 code?
A: It's possible to drive, but it's best to fix the issue soon to avoid fuel efficiency problems.
Q: Does this code affect gasoline engines?
A: No, it specifically affects vehicles with alternative fuel systems.
High-End · Full-system diagnostics
A full-system bidirectional platform aimed at advanced DIY users and professional diagnostic workflows.
Network faults often require full-system access instead of a generic code reader alone.
View on Amazon
Universal · Digital multimeter
A solid entry-level multimeter for voltage, continuity, resistance, and basic electrical troubleshooting.
Helpful for checking voltage drops, grounds, and basic circuit health when modules are not communicating.
View on Amazon
Universal · Wire connectors and repair kit
Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
View on AmazonThese are optional diagnostic tools, not guaranteed fixes. As an Amazon Associate I earn from qualifying purchases.