Auxiliary Climate Control System

WARNING: This page is about a different car, the 2004 Mercury Monterey and 2004 Ford Freestar. However, it is still accessible from the selected car via links, so may be relevant.

An auxiliary climate control system is available as optional equipment. The auxiliary climate control system operation is determined by the settings on the front or rear auxiliary climate control assembly. The auxiliary climate control assemblies include a blower motor switch, temperature control/air distribution mode knob, none of which can be individually serviced.

Auxiliary blower motor operation is enabled when the EMTC or EATC is in any mode except OFF. The auxiliary system air can be cooled below interior air temperature only when A/C compressor operation has been requested by the settings of the climate control assembly of the base (front) system. The auxiliary system air can be heated at any time.

The front auxiliary climate controls:

are built into the dual-zone EMTC or EATC module. The blower motor speed can be set to OFF, LO, MED LO, MED HI, or HI by pressing the auxiliary blower FAN button either right (higher) or left (lower).

The temperature/airflow mode can be adjusted by pressing the rear button either right (warm/floor) or left (cool/panel). If the front (main) driver side temperature is set to full cool or full heat, the auxiliary temperature will be set to the same as the driver and cannot be changed. When the front auxiliary REAR button is depressed, all control of the auxiliary climate control system functions are then transferred to the rear auxiliary climate control assembly and the auxiliary temperature can be fully independently controlled.

The rear auxiliary climate control assembly:

blower motor switch controls the auxiliary blower motor speed only when the front auxiliary climate control assembly blower motor switch is set to REAR. The blower motor speed can be set to OFF, LO, MED LO, MED HI, or HI.
temperature/airflow mode control switch is a potentiometer that outputs a variable voltage to the auxiliary temperature blend door actuator and auxiliary mode door actuator to set the position of the auxiliary temperature blend and mode doors only when the front auxiliary climate control assembly blower motor switch is set to REAR. When A/C compressor operation has not been initiated (A/C compressor commanded on) by the EMTC or EATC module (as equipped), the auxiliary climate control system cannot cool the air below that of the interior air temperature.