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 how hot or cold the battery coolant is, isn't working right. It's saying the sensor is reading a temperature that's too low.
The onboard computer has detected a low voltage signal from the Hybrid/EV battery pack coolant temperature sensor C, indicating that the sensor might be malfunctioning or the circuit is not working properly.
The P2D54 code is triggered when the powertrain control module (PCM) or hybrid control module detects a low voltage signal from the battery pack coolant temperature sensor C. This sensor is responsible for monitoring the temperature of the coolant used to regulate the battery pack's temperature. A low signal could indicate an issue with the sensor itself, the wiring, or the connection.
• Check Engine Light illuminated
• Possible overheating of the battery pack
• Reduced performance of the hybrid/EV system
• Faulty battery pack coolant temperature sensor
• Damaged or corroded wiring or connectors
• Faulty PCM or hybrid control module
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the battery pack coolant temperature sensor for proper operation.
• Replace the battery pack coolant temperature sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM or hybrid control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regular inspection of the cooling system
• Routine maintenance of electrical connections
• Ensure proper coolant levels
Sensor Issue
• Avoid driving long distances until the issue is resolved.
• Monitor the vehicle's temperature gauge closely.
Check with your vehicle manufacturer for warranty coverage on hybrid/EV components.
This code has become more common with the increase in hybrid and electric vehicles, highlighting the importance of battery temperature management.
Moderate – It should be addressed soon to prevent potential damage to the battery pack.
Ignoring this issue could lead to battery damage, which may be costly and affect vehicle safety.
• Vehicle should be in a safe, stationary position.
• Engine or system should be cool to prevent burns.
The battery pack coolant temperature sensor is typically located near the battery pack, within the cooling system.
Q: Can I drive with this code?
A: It's best to get it checked soon, as driving with this issue could lead to battery overheating.
Q: How is the sensor tested?
A: A multimeter can be used to check the sensor's resistance and voltage output.
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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.