Grand Caravan V6-4.0L (2008)
Blower Motor: Description and Operation
Operation - Front
OPERATION
The front blower motor is used to control the velocity of air moving through the front HVAC housing by spinning the blower wheel within the housing at
the selected or programed speed (depending on control application).
On models equipped with the manual temperature control (MTC) heating-A/C system, the front blower motor will operate whenever the ignition switch
is in RUN and the blower motor control is in any position except OFF. On models equipped with the automatic temperature control (ATC) heating-A/C
system, the front blower motor will operate whenever the ignition switch is in RUN and the A/C-heater control power is ON.
In the MTC system, the front blower motor speed is controlled by regulating the path to ground through the blower control switch and the blower motor
resistor. In the ATC system, the front blower motor speed is controlled by an electronic blower motor power module, which uses a pulse width
modulated input from the A/C-heater control and a feedback signal from the blower motor to regulate the blower motor ground path. On both systems,
the blower motor receives battery current through the totally integrated power module (TIPM) whenever the ignition switch is in RUN.
The blower motor and blower wheel are factory balanced and cannot be adjusted or repaired and must be replaced as an assembly if inoperative or
damaged.
