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 checks the electricity going to the air conditioner's motor is getting too much power.
The A/C compressor motor voltage sensor 'B' is detecting a voltage level that is higher than the expected range.
The P1D28 code indicates that the voltage sensor for the A/C compressor motor, specifically sensor 'B', is reading a voltage that exceeds the normal operating range. This could be due to a fault in the sensor itself, a wiring issue, or a problem with the A/C compressor's electrical system.
• Air conditioning not working properly
• Check Engine Light illuminated
• Unusual noises from the A/C system
• Faulty A/C compressor motor voltage sensor
• Wiring issues such as short circuits or open circuits
• Malfunctioning A/C compressor motor
A/C: Air Conditioning
Compressor: A device that increases the pressure of a gas by reducing its volume.
• Use a scan tool to verify the code and check for other related codes.
• Inspect the wiring and connectors for the A/C compressor motor voltage sensor.
• Test the voltage sensor for proper operation.
• Replace the faulty A/C compressor motor voltage sensor.
• Repair or replace damaged wiring or connectors.
• Replace the A/C compressor motor if necessary.
• OBD-II scan tool
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Honda Accord
• Acura TLX
• Honda Civic
• Regular maintenance of the A/C system
• Inspect wiring and connections periodically
• Avoid overloading the electrical system
Sensor Issue
• Have the vehicle inspected by a professional if the A/C is not working.
• Do not ignore the Check Engine Light.
Check with your vehicle manufacturer for warranty coverage on electrical components.
This code is often reported in vehicles with complex A/C systems and has been associated with electrical issues in newer models.
Moderate – It may affect comfort, but not immediate drivability.
Driving with a malfunctioning A/C system can lead to discomfort, especially in hot climates. Ensure repairs are done by qualified personnel.
• Vehicle must be running with the A/C system activated.
• Ensure all electrical connections are secure.
The A/C compressor motor voltage sensor is typically located near the A/C compressor, which is mounted on the engine.
Q: Can I drive with this code?
A: Yes, but the air conditioning may not work properly.
Q: Will this code affect my fuel efficiency?
A: Not directly, but a malfunctioning A/C system can put additional load on the engine.
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