This Preliminary Information communication provides information to the technician about vehicles that may have Diagnostic Trouble Code P2181 set. Technician will need to use a Technician 2 and test the engine coolant thermostat heater. If the coolant temperature does not reach 195 Fahrenheit (90 Celsius) within 5 minutes, replace the thermostat. Technician should also check to ensure the calibrations are up to date.
