Thermostat Diagnosis (LP1, LY7): Procedures
WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
The coolant thermostat can be tested using a temperature (tempil) stick. The temperature stick is a pencil-like device which has a wax material containing certain chemicals that melt at a given temperature. Temperature sticks can be used to determine a thermostat's operating range by rubbing 87°C (188°F) and 97°C (206°F) sticks on the outlet coolant pipe.
- Use a tempilstick in order to find the opening and the closing temperatures of the thermostat.
- J 24731 188 tempilstick melts at 87°C (188°F). See Special Tools . The thermostat should begin to open at 90°C (194°F).
- J 24731 206 tempilstick melts at 97°C (206°F). See Special Tools . The thermostat should be fully open at 107°C (225°F).
- Replace the thermostat if it does not operate properly between this temperature range.