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 has detected that the voltage going to the air conditioner's compressor motor is too low. It's like when a toy doesn't have enough battery power to work properly.
The vehicle's control module monitors the voltage levels of the A/C compressor motor. If it detects that the voltage is lower than expected, it triggers the P2D42 code.
The P2D42 code indicates that the voltage supplied to the A/C compressor motor circuit 'B' is below the threshold set by the manufacturer. This could be due to electrical issues such as a poor connection, a failing motor, or a problem with the power supply.
• A/C not cooling properly
• Unusual noise from the compressor
• Check engine light on
• Faulty A/C compressor motor
• Poor electrical connection
• Blown fuse or faulty relay
A/C: Air Conditioning
Compressor: A device that compresses refrigerant in the A/C system
• Check the A/C compressor motor and its connections.
• Inspect the fuses and relays related to the A/C system.
• Measure the voltage at the A/C compressor motor.
• Repair or replace the A/C compressor motor.
• Fix any poor connections or wiring issues.
• Replace blown fuses or faulty relays.
• Multimeter
• Socket set
• Wiring diagram
$200 - $800
Moderate
• Toyota Camry
• Honda Accord
• Ford Fusion
• Regularly inspect electrical connections.
• Check fuses and relays periodically.
• Ensure the A/C system is serviced regularly.
Electrical Issue
• Get the A/C system checked by a professional.
• Avoid using the A/C until the issue is resolved.
Check if your vehicle's warranty covers electrical components.
This code has been more common in vehicles with higher mileage or those that frequently use the A/C system.
Moderate – While not immediately dangerous, it should be addressed to ensure proper A/C function.
Driving with a malfunctioning A/C system is not a safety hazard, but it can lead to discomfort and further damage if not addressed.
• Vehicle at operating temperature
• A/C system turned on
The A/C compressor is typically located at the front of the engine bay, connected to the engine with a belt.
Q: Can I drive with this code?
A: Yes, but your A/C system may not work properly, leading to discomfort.
Q: Will this code affect my fuel efficiency?
A: Not directly, but running a malfunctioning A/C system might put extra load on the engine.
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