Defroster Door Motor Circuit

DEFROSTER DOOR MOTOR CIRCUIT


System Description


SYSTEM DESCRIPTION

Component Parts

Defroster door control system components are:
- A/C auto amp.
- A/C and AV switch assembly
- Defroster door motor
- PBR (Built into defroster door motor)
- In-vehicle sensor
- Ambient sensor
- Optical sensor
- Intake sensor

System Operation
The A/C auto amp. determines defroster door position based on the position of the defroster switch. When the defroster switch is depressed, the defroster door motor rotates directing air to the defroster ducts. When any mode other than defroster is selected, the defroster motor rotates in the opposite direction closing off air flow to the defroster ducts.
In the AUTO mode, the A/C auto amp. determines defroster door position based on the ambient temperature, the intake air temperature and the in-vehicle temperature.






COMPONENT DESCRIPTION

Defroster door motor





The defroster door motor is attached to the front heater & cooling unit assembly. The A/C auto amp. sends a voltage to rotate to the defroster door directing the air flow either to the defroster ducts, or to the floor ducts, depending on which way the voltage and ground are applied to the motor leads. Motor rotation is conveyed to a lever which activates the defroster door.