Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's battery pack is getting too hot because the sensor that checks its temperature is saying it's too high. It's like when you have a fever and the thermometer shows a high number.
The P1C02 code is triggered when the temperature sensor for the hybrid or electric vehicle's battery pack detects a temperature that is higher than the normal operating range.
This code indicates that the temperature sensor monitoring the coolant for the hybrid or electric vehicle's battery pack has detected a temperature that exceeds the manufacturer's specified limit. This could be due to a malfunctioning sensor, inadequate coolant flow, or an actual increase in battery temperature.
• Warning light on the dashboard
• Reduced vehicle performance
• Battery overheating
• Possible vehicle shutdown to prevent damage
• Faulty battery pack coolant temperature sensor
• Insufficient coolant flow
• Cooling system malfunction
• Actual overheating of the battery pack
OBD-II: On-Board Diagnostics, second generation
Coolant: A fluid used to transfer heat away from engine or battery components
• Check for any other related codes
• Inspect the coolant level and condition
• Test the battery pack coolant temperature sensor
• Inspect the cooling system components
• Replace faulty temperature sensor
• Refill or replace coolant
• Repair or replace defective cooling system components
• Ensure proper coolant flow
• OBD-II scanner
• Multimeter
• Coolant system pressure tester
$150 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly check and maintain coolant levels
• Ensure cooling system is functioning properly
• Schedule regular maintenance checks
Sensor Issue
• Do not ignore the warning light on the dashboard
• Schedule a service appointment if the code appears
• Avoid driving the vehicle if overheating is suspected
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 vehicle production, highlighting the importance of battery cooling systems.
High – Overheating can cause significant damage to the battery pack and should be addressed immediately.
Driving with an overheated battery pack can be dangerous and may lead to vehicle malfunction or fire.
• Vehicle is in operation
• Ambient temperature is within normal range
The battery pack coolant temperature sensor is typically located near the battery pack, often integrated into the cooling system.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to battery damage, reduced performance, or even a fire hazard.
Q: Can I drive my car with this code?
A: It is not recommended to drive the vehicle until the issue is diagnosed and repaired to prevent further damage.
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Universal · Digital multimeter
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Helpful for voltage, continuity, and basic electrical checks while narrowing down the fault.
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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.