Dynamic Test

1. Disconnect ground cable from battery.
2. Disconnect electric connector of thermotime switch.
3. Remove thermotime switch from thermostat housing.
4. Immerse heat-sensing portion of thermotime switch into cooling water maintained at 50° F.
5. When the thermotime switch temperature is just about the same as the cooling water temperature, measure the resistance between terminal 45 and 46. Resistance should be approximately 40 to 70 ohms.
6. Increase cooling water temperature at a rate of 1.8° F per second until it is more than 77° F then check continuity between terminal 45 and 46.
7. If the ohmmeter reading increases to infinite, circuit is satisfactory.