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 computer in your car thinks the sensor that measures how hot the radiator is, is not working right. It's saying the sensor is sending a signal that's too high.
The P00B4 code is triggered when the Engine Control Module (ECM) detects a high voltage signal from the radiator coolant temperature sensor circuit.
The radiator coolant temperature sensor is responsible for monitoring the temperature of the coolant in the radiator. If the sensor sends a voltage signal that is higher than expected, the ECM will set the P00B4 code. This could be due to a malfunctioning sensor, wiring issues, or a problem with the ECM itself.
• Check Engine Light is on
• Engine overheating
• Poor fuel economy
• Faulty radiator coolant temperature sensor
• Wiring issues such as shorts or open circuits
• Faulty ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the radiator coolant temperature sensor and its wiring.
• Test the sensor's voltage and resistance.
• Replace the radiator coolant temperature sensor.
• Repair or replace damaged wiring.
• Replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$100 - $300
Moderate
• Ford Focus
• Chevrolet Cruze
• Toyota Camry
• Regularly check coolant levels.
• Inspect wiring for damage.
• Replace sensors at recommended intervals.
Sensor Issue
• Do not ignore the Check Engine Light.
• Monitor engine temperature closely.
• Seek professional help if unsure about repairs.
Check with your vehicle manufacturer; sensor-related issues might be covered under powertrain warranty.
This code has been associated with sensor failures in vehicles with high mileage or poor maintenance history.
Moderate – While the vehicle may still be drivable, ignoring the issue can lead to engine overheating.
Driving with an overheating engine can cause severe damage and is a safety risk.
• Engine at normal operating temperature
• Vehicle parked and engine idling
The radiator coolant temperature sensor is typically located near the radiator or thermostat housing.
Q: Can I drive my car with a P00B4 code?
A: It's not recommended as it can lead to engine overheating and further damage.
Q: How do I reset the Check Engine Light after fixing the issue?
A: You can use an OBD-II scanner to clear the code after repairs are completed.
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Universal · Digital multimeter
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Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
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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.