Originally Posted by martysmartie

You replace, for the CTS you would need to know the resistance VS temp scale, for the price you would just buy a new one.

For the fan switch you can check the continuity of a hot engine or heat up a saucepan, as said.

Martin

Originally Posted by Rogeyboy

Put em in a saucepan, slowly heat the water up to boiling. Use a thermometer and see when they activate using a multimeter i guess?