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 voltage for the A/C coolant heater is getting too much power.
The A/C coolant heater voltage sensor monitors the voltage level of the A/C coolant heater. If the voltage is higher than expected, the sensor triggers this code.
The P1D46 code is set when the Powertrain Control Module (PCM) detects a voltage reading from the A/C coolant heater voltage sensor that is higher than the specified range. This could indicate a problem with the sensor itself, the wiring, or the heater circuit.
• Check Engine Light illuminated
• A/C system not functioning properly
• Possible decrease in fuel efficiency
• Faulty A/C coolant heater voltage sensor
• Wiring issues such as short circuits or open circuits
• Faulty PCM
PCM: Powertrain Control Module
A/C: Air Conditioning
• Use an OBD-II scanner to confirm the code.
• Inspect the A/C coolant heater voltage sensor and its wiring.
• Check for any blown fuses related to the A/C system.
• Replace the A/C coolant heater voltage sensor if faulty.
• Repair or replace damaged wiring.
• Replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $500
Moderate
• Honda Accord
• Honda Civic
• Acura MDX
• Regularly inspect A/C system components.
• Perform routine maintenance checks.
• Ensure proper electrical connections.
Sensor Issue
• Have the vehicle inspected by a professional.
• Avoid using the A/C until the issue is resolved.
Check if the vehicle's warranty covers electrical components.
This code is relatively uncommon and often related to specific vehicle models with known A/C system issues.
Moderate – While the vehicle may still be drivable, it is important to address the issue to prevent further damage.
Driving with a malfunctioning A/C system can lead to discomfort and potential safety issues due to fogged windows.
• Vehicle at normal operating temperature
• A/C system activated
The A/C coolant heater voltage sensor is typically located near the A/C compressor or within the engine bay.
Q: Can I drive with the P1D46 code?
A: It's possible, but not recommended as it may lead to further issues with the A/C system.
Q: Will fixing this code improve my fuel efficiency?
A: Yes, resolving A/C system issues can help improve fuel efficiency.
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