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 the car's computer thinks the sensor that measures pressure in the hydraulic pump for alternative fuel is showing a number that's too high.
The vehicle's computer has detected a voltage signal from the hydraulic pump pressure sensor that is higher than the expected range.
The P2A78 code indicates that the sensor circuit that monitors the pressure in the hydraulic pump for alternative fuel is sending a signal that is higher than the predetermined threshold. This could be due to a malfunctioning sensor, wiring issues, or a problem with the hydraulic pump itself.
• Check Engine Light is on
• Reduced fuel efficiency
• Poor engine performance
• Faulty hydraulic pump pressure sensor
• Wiring issues or poor electrical connections
• Malfunctioning hydraulic pump
Hydraulic Pump: A device that moves fluid by mechanical action.
Pressure Sensor: A device that measures pressure in a system and sends data to the computer.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the pressure sensor.
• Test the hydraulic pump pressure sensor with a multimeter.
• Replace the hydraulic pump pressure sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Check and replace the hydraulic pump if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Toyota Prius
• Honda Civic Hybrid
• Chevrolet Volt
• Regularly inspect and maintain the fuel system.
• Ensure all electrical connections are secure.
• Use quality alternative fuels.
Sensor Issue
• Have your vehicle inspected by a professional if the Check Engine Light comes on.
• Do not ignore the warning signs as it may lead to further damage.
• Consider regular maintenance checks to prevent such issues.
Check with your vehicle manufacturer to see if the sensor or related components are covered under warranty.
This code is relatively uncommon and typically appears in vehicles utilizing alternative fuel systems.
Moderate – Address the issue to prevent potential damage to the fuel system.
Driving with a malfunctioning fuel system sensor can lead to increased emissions and potential safety risks.
• Vehicle should be running.
• Ensure the fuel system is pressurized.
The hydraulic pump pressure sensor is typically located near the hydraulic pump, which is part of the vehicle's fuel system.
Q: Can I drive my car with a P2A78 code?
A: It's not recommended to drive for long periods with this code active, as it may lead to further damage.
Q: What happens if I ignore this code?
A: Ignoring this code can result in poor fuel efficiency and potential damage to the fuel system.
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