The automobile coolant temperature switch,that is widely known as the coolant temperature sensor, is a switch in the engine that reads the engine coolant temperature and then transmits a signal to the engine control module, or ECM, to control other duties of engine operation like the air-fuel ratio.

It is equally called a switch because on some vehicle, it is used to turn on the engine cooling fan at a specified temperature. This assist in the engine warm-up process as well as preserving the engine at a safe operating temperature.

Facts to Know:

The coolant temperature switch is animportant part of the cooling system. If it gets defective, it can create severe internal engine damage becauseof overheating, incorrect air-fuel ratio, or incorrect ignition timing. It can eqaully cause shorter life to the cooling fan motor or other electrical devices of the cooling system.

Some cars are furnished with a separate sensor to show the engine temperature to the driver through the temperature gauge.

How to Repair:

If thecoolant Temperature Switch is seen to require replacement. The coolant is drained until the switch is seen.

The faulty Coolant Temperature Switch should be taken out by disconnecting the connector and taking it from the manifold.

The new Coolant Temperature Switch is put into the mounting hole in the manifold and the electrical connector is reconnected. The coolant is then refilled.

The Coolant Temperature Switch is then tested for operation, codes are cleared, and retested to ensure all codes have been fixed.

The car is road tested to ensure proper operation of the Cooling System.

If you feel that your coolant temperature switch has gone bad,a mechanic come out straightaway to analyze the issue.

Common symptoms showing you may have to changeCoolant Temperature Switch (Sensor):

Check Engine light on

Engine overheating

Cooling fan runs erratically

Engine misfires, stalls, or idles roughly

Intermittent coolant temperature

Importance of this service:

This component, when defective, could make the fan to run erratically or not at all, which in turns produces overheating or overuse of the cooling fan motor. Whenever overheating happens, severe engine damage is a possibility.

The car engine air-fuel ratio is what keeps it operating smoothly. If the ratio gets skewed in any way, the engine will have poor fuel economy and function poorly or not at all. The coolant temperature switch is important because it feeds the ECM with the information it requires to make this calculation and operate the engine optimally.