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 controls the fuel pump for alternative fuels. It's like a switch that isn't working right, so the car can't use the alternative fuel properly.
The P2A85 code indicates a low voltage or malfunction in the circuit controlling the compression stroke valve of the alternative fuel pump B.
The P2A85 code is triggered when the Engine Control Module (ECM) detects a low voltage condition in the control circuit for the compression stroke valve of the alternative fuel pump B. This could be due to a faulty valve, wiring issues, or a malfunctioning ECM.
• Check Engine Light is on
• Reduced fuel efficiency
• Difficulty in switching to alternative fuel
• Faulty alternative fuel pump B compression stroke valve
• Damaged or corroded wiring or connectors
• Faulty Engine Control Module (ECM)
ECM: Engine Control Module, the computer that controls the engine's functions
Alternative Fuel: Fuel that is not derived from petroleum, such as ethanol or natural gas
• Use an OBD-II scanner to confirm the code
• Inspect wiring and connectors for damage or corrosion
• Test the alternative fuel pump B compression stroke valve
• Replace or repair damaged wiring or connectors
• Replace the faulty compression stroke valve
• Reprogram or replace the ECM if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Toyota Prius
• Honda Civic Hybrid
• Chevrolet Volt
• Regular maintenance and inspection of fuel system components
• Ensure proper connections and condition of wiring harnesses
• Use quality fuel and additives as recommended by the manufacturer
Sensor Issue
• Avoid switching to alternative fuel until the issue is resolved
• Consult a professional mechanic for accurate diagnosis and repair
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
The P2A85 code has been reported in vehicles with alternative fuel systems, particularly in hybrid models.
Moderate – It should be addressed soon to ensure proper fuel efficiency and vehicle performance.
Driving with a malfunctioning fuel system can lead to increased emissions and reduced vehicle performance.
• Engine running
• Alternative fuel system engaged
The alternative fuel pump B and its compression stroke valve are typically located near the fuel tank or along the fuel line.
Q: Can I drive my car with the P2A85 code?
A: It's possible to drive the car, but it may not perform optimally, especially when using alternative fuel. It's best to get it checked soon.
Q: Will this code affect my car's emissions?
A: Yes, a malfunction in the fuel system can lead to increased emissions.
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