Rendezvous AWD V6-3.6L VIN 7 (2004)
Air Door Actuator / Motor: Description and Operation
HVAC System - Automatic
MODE ACTUATOR
The mode actuator is a 5 wire bi-directional electric motor that incorporates a feedback potentiometer. Ignition 3 voltage, low reference, control, 5
volt reference and position signal circuits enable the actuator to operate. The control circuit uses either a 0, 2.5 or 5 volt signal to command the
actuator movement. When the actuator is at rest, the control circuit value is 2.5 volts. A 0 or 5 volt control signal commands the actuator movement in
opposite directions. When the actuator shaft rotates, the potentiometer's adjustable contact changes the door position signal between 0-5 volts.
The HVAC control module uses a range of 0-255 counts to index the actuator position. The door position signal voltage is converted to a 0-255 count
range. When the module sets a commanded, or targeted, value, the control signal is changed to either 0 or 5 volts depending upon the direction that
the actuator needs to rotate to reach the commanded value. As the actuator shaft rotates the changing position signal is sent to the module. Once the
position signal and the commanded value are the same, the module changes the control signal to 2.5 volts
RECIRCULATION ACTUATOR
The recirculation actuator is a 3 wire bi-directional electric motor. Ignition 3 voltage, ground and control circuits enable the actuator to operate. The
control circuit is either grounded or opened during normal operation. If the control circuit is grounded, then the shaft rotates in the opposite direction
than it would if the circuit was opened. The actuator shaft rotates until the limit is reached. If the module needs to reverse the direction of rotation,
then the control circuit's state is reversed. The open circuits are held at ignition 3 voltage from the actuator. The module will maintain the control
circuit's state until a new position is needed.
AIR TEMPERATURE ACTUATOR
The air temperature actuator is a 5-wire bi-directional electric motor that incorporates a feedback potentiometer. Ignition 3 voltage, low reference
control, 5-volt reference and position signal circuits enable the actuator to operate. The control circuit uses either a 0, 2.5 or 5-volt signal to command
the actuator movement. When the actuator is at rest, the control circuit value is 2.5 volts. A 0 or 5-volt control signal commands the actuator
movement in opposite directions. When the actuator shaft rotates, the potentiometer's adjustable contact changes the door position signal between 0-5
volts. The HVAC control module uses a range of 0-255 counts to index the actuator position. When the module sets a commanded, or targeted, value,
the control signal is changed to either 0 or 5 volts depending upon the direction that the actuator needs to rotate to reach the commanded value. As the
actuator shaft rotates the changing position signal is sent to the module. Once the position signal and the commanded value are the same, the module
changes the control signal to 2.5 volts.
