Auxiliary Heating Operation
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With the auxiliary rear heater (C36) option, there is no auxiliary A/C system. This system has only a blower motor switch to regulate air speed. It does not use a air temperature actuator or a mode actuator. The lowest blower speed will have high auxiliary duct temperature. The highest blower speed will have low auxiliary duct temperature. The slower the air travels past the auxiliary heater core the more time it has to absorb heat.