Using Multi Meter

WARNING: This page is about a different car, the 2004 Kia Amanti. However, it is still accessible from the selected car via links, so may be relevant.

With the temperature sensing portion of Water Temperature Sensor (WTS) immersed in hot engine coolant, check the resistance.

Fig 1: Illustrating WTS Resistance Chart
Courtesy of KIA MOTORS AMERICA, INC.

Fig 2: Testing WTS Resistance
Courtesy of KIA MOTORS AMERICA, INC.
If the resistance deviates from the standard value greatly, replace the sensor.