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A modern-day automobile relies on sophisticated performance enhancing and monitoring systems that take a lot of the guesswork away from the owner. However, these systems are only as strong as some of the simplest sensors throughout the vehicle, such as the one that measures coolant temperature.



What is a Coolant Temperature Sensor?

To ensure that the vehicle’s engine and ancillaries work together in harmony, the central computer relies on several devices to gather and send information. The computer will be looking for a regular stream of information relating to the temperature of the all-important coolant, so that the operation of the motor can be safeguarded and optimized and the coolant temperature sensor provides this data.

How Does a Coolant Temperature Sensor Works?

Usually, the coolant temperature sensor is located very close to the engine’s thermostat and the sensor is designed to record the temperature of the coolant by measuring the liquid directly or connecting to the thermostat. On a regular basis, the temperature is sent through to the computer which will decide if it is in the optimal range and if not, alterations are made to other components to help achieve this.

In a worst-case scenario, the computer could switch off the engine, but usually it will send a signal to activate the cooling fan, or may even adjust the fuel to air mixture within the combustion chamber. The computer will then continue to monitor the data provided by the sensor to see if such changes made the necessary difference and if not, to continue with other options. All this action takes place within a very short time span and is part of a constant process and if a fault develops or the computer is not able to adjust operating conditions effectively, it will also activate a warning light on the dashboard to inform the driver.

How Is a Coolant Temperature Sensor Made?

Due to its proximity to high temperatures, the coolant temperature sensor is typically contained within a metal housing. It will be attached to a connector with two wires, one of which provides some low voltage and the other that sends the information back to the computer. Inside the housing is a material that measures resistance caused by temperature changes.

How Does a Coolant Temperature Sensor Fail?

  • Affected by condensation
  • Electrical connections fail
  • Sensor develops a fault

What Are the Symptoms of Failure?

  • Overheating engine
  • Poor engine performance
  • Permanent dashboard warnings or “check engine light” signals

What Are the Consequences of Failure?

  • Engine damage

The engine coolant temperature sensor has a crucial role to play in not only helping to achieve optimal performance, but avoiding costly damage due to poor operating conditions.

f you have questions or concerns about Coolant Temperature Sensors or any of your vehicle’s components, come into your local Pep Boys where we can answer any question, help you find any part, or perform any vehicle service you might need.