Component Description

WARNING: This page is about a different car, the 2016 Infiniti QX60. However, it is still accessible from the selected car via links, so may be relevant.

Component		Description
A/C auto amp.		A/C auto amp. controls the automatic air conditioning system by inputting and calculating signals from each sensor and each switch.
Multifunction switch		Rear air control operation signal is transmitted from the multifunction switch to AV control unit via AV communication line.
Air mix door motor (Rear)		The air mix door (rear) controls the mix of hot or cold air that enters the ventilation system. It is controlled by the A/C auto amp. based on the position of the temperature dial. The air mix door motor (rear) receives position commands from the A/C auto amp. and reports actual door position back via an LCU (Local Control Unit) installed inside the motor. Commands and responses are sent across the LIN (Local Interconnect Network) to each motor simultaneously, with each motor having its own unique address, thereby only responding to requests sent to its specific address. The LCU reads the door position from a Position Balanced Resistor (PBR), also part of the motor, and returns that information to the A/C auto amp.. The LCU switches the polarity of the circuits connected to the DC motor to drive the motor forward or backward as requested by the front air control. If the air mix door (rear) moves to a position less than 5% or more than 95% of its expected or allowed positions, the A/C auto amp. will set a DTC.
AV control unit		AV control unit transmits multifunction switch operation signal to A/C auto amp. via CAN communication line.
BCM		BCM transmits blower motor ON signal to the rear blower motor relay.
Display unit		The display unit indicates operation status of the front and rear automatic air conditioning system.
Mode door motor (Rear)		The mode door (rear) controls the direction the conditioned air passes through the ventilation system. The mode door motor (rear) receives position commands from the A/C auto amp. and reports actual door position back via an LCU (Local Control Unit) installed inside the motor. Commands and responses are sent across the LIN (Local Interconnect Network) to each motor simultaneously, with each motor having its own unique address, thereby only responding to requests sent to its specific address. The LCU reads the door position from a Position Balanced Resistor (PBR), also part of the motor, and returns that information to the front air control. The LCU switches the polarity of the circuits connected to the DC motor to drive the motor forward or backward as requested by the A/C auto amp.. The mode door has 2 expected positions and, therefore, can set up to 2 DTCs if the expected position is not reported back to the A/C auto amp.
PTC heater		The positive temperature coefficient (PTC) heater provides supplemental heat to the rear seating by warming the air as it flows through its electrically controlled heating grid.
PTC heater relay		The PTC heater relay controls the flow of current to the PTC heater. The relay is controlled by the A/C auto amp.
Rear blower motor 1		The rear blower motor-1 varies the speed at which the air flows through the ventilation system.
Rear blower motor 2		The rear blower motor-2 varies the speed at which the air flows through the ventilation system.
Rear blower motor relay		The rear blower motor relay controls the flow of current to the rear blower motor. The relay is connected directly to ground, and is controlled by the BCM.
Rear shut-off door motor		The rear shut-off door controls the conditioned air through the ventilation system. The rear shut-off door motor receives position commands from the A/C auto amp. and reports actual door position back via an LCU (Local Control Unit) installed inside the motor. Commands and responses are sent across the LIN (Local Interconnect Network) to each motor simultaneously, with each motor having its own unique address, thereby only responding to requests sent to its specific address. The LCU reads the door position from a Position Balanced Resistor (PBR), also part of the motor, and returns that information to the front air control. The LCU switches the polarity of the circuits connected to the DC motor to drive the motor forward or backward as requested by the A/C auto amp.. The mode door has 2 expected positions and therefore will set a DTC if the expected position is not reported back to the A/C auto amp.