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 found a problem with the sensors that check the temperature of the liquid that keeps the hybrid or electric car's battery cool. It's like when a thermometer doesn't agree with another thermometer on how hot or cold something is.
The car's computer monitors the temperature of the coolant in the hybrid/EV battery pack using multiple sensors. This code is triggered when the readings from Sensor A and Sensor B do not match or correlate as expected.
The P2D2B code is set when the Engine Control Module (ECM) or Battery Management System (BMS) detects a discrepancy between the temperature readings from two coolant temperature sensors (A and B) in the hybrid/EV battery pack. This could indicate a sensor malfunction, wiring issue, or a problem with the coolant system itself.
• Check Engine Light is on
• Reduced battery performance
• Possible overheating of the battery pack
• Faulty coolant temperature sensor A or B
• Wiring issues or poor connections
• Coolant system malfunction
ECM: Engine Control Module
BMS: Battery Management System
• Check for any other related codes
• Inspect the wiring and connections of the sensors
• Test the functionality of both sensors
• Replace faulty sensor
• Repair or replace damaged wiring
• Ensure coolant system is functioning properly
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $400
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect coolant system
• Check sensor connections periodically
• Ensure proper maintenance of the battery pack
Sensor Issue
• Do not ignore the Check Engine Light
• Get the vehicle inspected by a professional
• Monitor battery performance for any changes
Check with your vehicle manufacturer; battery and related components might be under warranty.
This code is relatively new and specific to hybrid and electric vehicles as they become more common.
Moderate – It is important to address this issue to prevent potential battery damage.
Ignoring this code could lead to battery overheating, which might be a safety hazard.
• Vehicle should be at operating temperature
• Ensure the battery is under load for accurate readings
The sensors are typically located near the battery pack, often integrated into the coolant lines or the battery casing.
Q: Can I drive with this code?
A: It's not recommended to drive for long periods with this code, as it may lead to battery damage.
Q: How do I reset the code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, it should not return.
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Fitment Required · Vehicle-fitment part
Relevant when coolant-temperature and warm-up faults indicate a thermostat-related issue.
Coolant-temperature and warm-up faults often lead to thermostat testing and replacement.
Thermostats are vehicle-specific and should be matched by engine and housing style.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.