Testing the Function Of the Operating Thermostat

WARNING: This page is about a different car, the 2002 Volvo C70, 2001 Volvo C70, 2000 Volvo C70, 1999 Volvo C70, and 1998 Volvo C70. However, it is still accessible from the selected car via links, so may be relevant.

Remove the operating thermostat.

Fig 1: Identifying Ohmmeter
Courtesy of VOLVO CARS OF NORTH AMERICA.
- Connect an ohmmeter across both operating thermostat terminals.
- Heat the thermostat to a temperature above 93°C
- The operating thermostat must open at approximately 90°C
- Allow the thermostat to cool to a temperature below 55°C
- The operating thermostat must close at approximately 60°C

Does the operating thermostat open and close at the given values?

YES
Refer to Checking the Heater Controls .
NO
Refer to Replacing the Component