Automatic Temperature Control System
AUTOMATIC TEMPERATURE CONTROL SYSTEM
The automatic temperature control (ATC) system will activate the supplemental cabin heater based on engine coolant temperature and interior component settings. The cabin heater can operate in a full or partial load range as well as an idle mode all dependent on the engine coolant temperature. The cabin heater will also turn off if the A/C-heater temperature control is lowered to less than the lower set point. The cabin heater can take up to three minutes to completely shut down when either the heater temperature is set below the lower set point or the vehicle ignition is shut down.
NOTE: Do not apply a strong vacuum source such as a garage ventilation system directly on the supplemental cabin heater exhaust line. Too strong of a vacuum can prevent the supplemental cabin heater from starting. If required, place the vacuum source at least 75 mm (3 in.) away from the exhaust line.
The supplemental cabin heater only operates when the engine is running, the mileage exceeds 8 kilometer (5 mph) and the fuel tank volume exceeds 1/8 of a tank. The supplemental heater control module monitors blower speed and combustion during its start-up. The cabin heater should operate if the coolant temperature is below 40° C (104° F).