Heater, Ventilation System
Heater, Ventilation SystemFunctional and Operational Description
Heater
After the engine warms up, the heater system uses the warm engine coolant to supply warm air to the vehicle interior.
Outside air is supplied to the vehicle interior through the heater core of the heater unit.
Temperature inside the vehicle is adjusted appropriately by controlling the mixture of air between the outside air and heater core.
Temperature of the air that is supplied to the vehicle interior is controlled using the temperature control knob. This knob controls air temperature inside the vehicle by opening/closing the air mix door of the heater unit to control the amount of air that passes through the heater core.
Use the air selector knob to select an arbitrary air outlet inside the vehicle by altering the mode accordingly.
Use the air source selector lever to select "outside air intake" or "inside air circulation". Set this to "FRESH" to enable intake of outside air at all times. (Inside air will also be partially mixed.) Set the lever to "RECIRC" to enable inside air circulation without intaking outside air. Doing so speeds up heating of the vehicle interior by the heater, but this may cause fogging of the front window. To prevent fogging, set to "FRESH".
Control Lever ASM
The control lever ASM enables selection of air outlet of the heater, temperature adjustment, and switching between inside and outside air of the blower ASM via the cable. The fan control is used to control the amount of air sent out at four levels from "Low" to "High", by a resistor.
Legend
(1) Air Selector Knob
(2) Air-source Selector Lever
(3) Temperature Control Knob
(4) Air Conditioning Switch (with A/C)
(5) Fan Control Knob (Fan Control Switch)
Fan Control Knob (Fan Control Switch)
Use this knob to control the blower motor rotation via the resistor, thereby adjusting the amount of air to be supplied to defrost, foot and the ventilator.
The knob has four different setting positions.
1. LOW
2. MEDIUM LOW
3. MEDIUM HIGH
4. HIGH
Air-source Selector Lever
Slide this lever to the left or right to select either "FRESH" or "RECIRC".
Ventilation
If the air source select lever is moved to the "FRESH" position, a constant supply of outside air is introduced into the cabin. (For improved heating performance, a portion of the inside air is mixed with the air being introduced from outside by way of the blower ASM's inside air intake door.)
The blower fan brings outside air into the vehicle's cabin, and works to correctly maintain ventilation.
If the air source select lever is moved to the "RECIRC" position, the air inside the cabin is constantly circulated, without air from outside being introduced.
Legend
(1) Intake Door
(2) Inside Air Filter
(3) Outside Air Filter
(4) Blower Fan
(5) Blower Motor
(6) Inside Air Intake Door
Air Selector Knob
The air select knob supplies air to the vehicle interior through the various outlets.
The vent blowing air changes due to an adjustment of the position of the two types of rotary style mode door inside the heater unit. These mode doors adjust the opening range of each vent from the heater unit, cut off the opening, and ventilate the door's interior, allowing for six different blow patterns to be selected.
- FACE: Setting to this position supplies air to the vehicle interior through the ventilation duct (1 and 2). Control the amount of air using the fan control knob (fan control switch).
- BI-LEVEL: Setting to this position supplies air to the vehicle interior by dividing air in the heater unit into two levels (1, 2 and 5). When the temperature control knob is set to the center position, air that is supplied to the feet through the foot duct (5) is set to a higher temperature than the air that is supplied through the ventilation duct (1 and 2).
- FOOT: Setting to this position supplies the entire amount of air to the feet through the foot duct (5).
- DEF/FOOT-1: Setting to this position supplies a smaller amount of air to the feet (5) than the "FOOT" mode, and a small amount of air is supplied for defrosting (3 and 4).
- DEF/FOOT-2: Setting to this position increases the amount of air for defrosting (3 and 4) as compared with DEF/FOOT-1, and decreases the amount of air to be supplied to the feet (5).
- DEFROST: Setting to this position supplies a large proportion of the air to the front window (4) and a small amount of air to the side windows (3).
Legend
(1) Mode Door (FACE)
(2) Evaporator Core (with A/C)
(3) Air Mix Door
(4) Heater Core
(5) Mode Door (FOOT/DEF)
Legend
(1) Mode Door (FACE)
(2) Evaporator Core (with A/C)
(3) Air Mix Door
(4) Heater Core
(5) Mode Door (FOOT/DEF)
Temperature Control Knob
Setting the temperature control knob to the "MAX COLD" position closes the air mix door and shuts out air flow into the heater core. Setting the knob to the "MAX HOT" position opens the air mix door, thereby enabling heating of the vehicle interior via air through the heater core.
Setting the knob to the center position enables adjustment of the temperature inside the vehicle by increasing or decreasing the air supply to the heater core.
MAX HOT (FACE MODE)
Legend
(1) Mode Door (FACE)
(2) Air Mix Door
(3) Evaporator Core (with A/C)
(4) Heater Core
(5) Mode Door (FOOT/DEF)