General Description, Smartway Certified Parked Heater
P4 DM Ch9; CasGen5 DM Ch7
All vehicles equipped with diesel operated coolant heaters are 'Smartway Certified.' The coolant heater will keep the engine coolant between approximately 150 and 180°F (65 and 82°C). Heated coolant is routed through the auxiliary HVAC heater core to allow heater-only function of the auxiliary HVAC system.
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