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 a sensor in a hybrid or electric car that checks the temperature of the coolant is reading too high. It's like a thermometer saying it's really hot when it shouldn't be.
The P2B27 code indicates that the vehicle's onboard computer has detected a high voltage signal from the Hybrid/EV Electronics Coolant Temperature Sensor C, suggesting that the temperature reading is higher than expected.
The Hybrid/EV Electronics Coolant Temperature Sensor C is responsible for monitoring the temperature of the coolant used to cool the electronic components in a hybrid or electric vehicle. A 'Circuit High' code means that the sensor is reporting a higher than normal voltage, which typically indicates a higher than normal temperature reading.
• Check Engine Light is on
• Possible overheating of electronic components
• Reduced vehicle performance
• Increased cooling fan activity
• Faulty coolant temperature sensor
• Wiring issues such as shorts or open circuits
• Faulty or damaged connectors
• Malfunctioning control module
OBD-II: On-Board Diagnostics, a standardized system for self-diagnostics in vehicles.
Coolant: A fluid used to transfer heat away from engine components.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the coolant temperature sensor for proper operation.
• Check for any other related codes.
• Replace the faulty coolant temperature sensor.
• Repair or replace damaged wiring or connectors.
• Reset the vehicle's computer and clear the code.
• Test drive the vehicle to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regular maintenance checks
• Ensure proper coolant levels
• Inspect wiring and connectors periodically
Sensor Issue
• Avoid driving the vehicle until the issue is resolved to prevent damage.
• Consult a professional mechanic for accurate diagnosis and repair.
Check with the vehicle manufacturer for warranty coverage on hybrid/EV components.
This code has been reported in hybrid and electric vehicles as they rely more on electronic components that require proper cooling.
Moderate – Addressing this issue promptly can prevent potential damage to the vehicle's electronic components.
Ignoring this issue may lead to overheating, which can cause damage to the vehicle and pose safety risks.
• Vehicle at operating temperature
• Engine running
The coolant temperature sensor is typically located near the radiator or coolant lines in the engine compartment.
Q: Can I drive with a P2B27 code?
A: It's not recommended to drive with this code as it may lead to overheating and damage to electronic components.
Q: How do I clear a P2B27 code?
A: After repairs, use an OBD-II scanner to clear the code from the vehicle's computer.
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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.