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 that checks the temperature of the coolant in a hybrid or electric vehicle is reading too high. It's like a thermometer saying it's too hot when it shouldn't be.
The P2B23 code is triggered when the powertrain control module (PCM) detects a high voltage signal from the Hybrid/EV Electronics Coolant Temperature Sensor B. This indicates that the sensor is reading a temperature that is higher than expected.
The Hybrid/EV Electronics Coolant Temperature Sensor B is responsible for monitoring the temperature of the coolant that cools the electronic components in a hybrid or electric vehicle. A circuit high condition indicates that the sensor is sending a higher voltage signal than the PCM expects, which could be due to a malfunctioning sensor or issues with the wiring or connections.
• Check Engine Light is on
• Overheating warning light
• Reduced vehicle performance
• Possible cooling fan issues
• Faulty coolant temperature sensor
• Wiring issues such as shorts or open circuits
• Poor electrical connections
• Faulty PCM
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the coolant temperature sensor and its wiring.
• Check for any loose or corroded connections.
• Test the sensor's resistance and voltage output.
• Replace the faulty coolant temperature sensor.
• Repair or replace damaged wiring.
• Clean and secure electrical connections.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$100 - $300
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly check and maintain coolant levels.
• Inspect wiring and connections for damage.
• Ensure the cooling system is functioning properly.
Sensor Issue
• Avoid driving the vehicle until the issue is fixed to prevent overheating.
• Consult a professional mechanic for accurate diagnosis and repair.
Check with the vehicle manufacturer for warranty coverage on sensors and electronic components.
This code has been reported in hybrid and electric vehicles with cooling system issues, often related to sensor failures.
Moderate – While the vehicle may still be drivable, ignoring this issue could lead to overheating and more severe damage.
Driving with a faulty coolant temperature sensor can lead to overheating, which may cause engine damage or pose a safety risk.
• Engine at operating temperature
• Vehicle in a safe, stationary position
The Hybrid/EV Electronics Coolant Temperature Sensor B is typically located near the electronic components it monitors, often in the engine bay or near the battery pack.
Q: Can I drive my car with the P2B23 code?
A: It's not recommended as it could lead to overheating and further damage.
Q: How can I reset the P2B23 code?
A: After repairs, 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 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.