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 one of the sensors that checks the temperature in the heat pump is showing a very low reading, like when something is too cold.
The P1D71 code is triggered when the temperature sensor 'B' in the heat pump circuit sends a signal to the car's computer that is below the expected range.
The P1D71 code indicates a problem with the heat pump temperature sensor 'B', which is responsible for monitoring the temperature within the heat pump system. A 'circuit low' condition suggests that the sensor is sending a voltage signal that is lower than the normal operating range, possibly due to a malfunction or a wiring issue.
• Check Engine Light is on
• Poor heating performance
• Unusual temperature readings
• Faulty heat pump temperature sensor 'B'
• Damaged wiring or connectors in the sensor circuit
• Short circuit to ground in the sensor wiring
Heat Pump: A system that transfers heat energy from a source to a thermal reservoir.
Temperature Sensor: A device that measures temperature and sends this information to the vehicle's computer.
• Use an OBD-II scanner to confirm the code and check for other related codes.
• Inspect the wiring and connectors for damage or corrosion.
• Test the heat pump temperature sensor 'B' for proper operation.
• Replace the faulty heat pump temperature sensor 'B'.
• Repair or replace damaged wiring or connectors.
• Clear the code and test drive to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Wrench set
$100 - $300
Moderate
• Honda Accord Hybrid
• Toyota Prius
• Chevrolet Volt
• Regularly inspect and maintain the heat pump system.
• Ensure wiring and connectors are secure and free from corrosion.
• Perform routine diagnostic checks.
Sensor Issue
• Have the vehicle inspected by a professional if the Check Engine Light is on.
• Avoid ignoring the issue, as it may affect heating performance.
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
This code has been associated with hybrid and electric vehicles using heat pump systems for climate control.
Moderate – Address the issue soon to prevent heating problems.
Driving with a faulty sensor can lead to improper climate control operation, affecting comfort and safety.
• Engine running
• Heat pump system activated
The heat pump temperature sensor 'B' is typically located within the heat pump system, often near the evaporator or condenser.
Q: Can I drive with a P1D71 code?
A: You can drive, but it's best to have it checked soon to avoid heating issues.
Q: How can I reset the P1D71 code?
A: Use an OBD-II scanner to clear the code, but ensure the issue is fixed first.
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Fitment Required · Vehicle-fitment part
Relevant when EVAP diagnosis points toward purge-flow or purge-control faults.
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