Thermostat Test

WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2017 Honda Odyssey, 2016 Honda Odyssey, 2015 Honda Odyssey, 2014 Honda Odyssey, and 2013 Honda Odyssey. However, it is still accessible from the selected car via links, so may be relevant.

Replace the thermostat if it is stuck in the open position at room temperature.

To test a closed thermostat:

Suspend the thermostat (A) in a container of water. Do not let the thermostat and the thermometer (B) touch the bottom of the hot container.

Fig 1: Identifying Thermostat Opening Temperature
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Heat the water and check the temperature with a thermometer. Check the temperature at which the thermostat first opens, and at which it is fully open.
Measure the lift height of the thermostat when it is fully open.
Standard Thermostat

Lift Height: Above 10.0 mm (0.394 in)

Starts Opening: 169-176 °F (76-80 °C)

Fully Open: 194°F (90°C)