System Diagram

System Description

DESCRIPTION

• Manual air conditioning system is controlled by each function of thermo control amp., BCM, ECM and IPDM E/R.

• Fan speed of blower motor is changed by the combination of fan control dial operation and blower fan resistor control.

CONTROL BY THERMO CONTROL AMP.

HAC-203, "Compressor Control"

CONTROL BY BCM

HAC-203, "Compressor Control"

CONTROL BY ECM

• HAC-203, "Compressor Control" • Cooling fan control: Refer to EC-61, "COOLING FAN CONTROL : System Description".

CONTROL BY IPDM E/R
• HAC-203, "Compressor Control" • Cooling fan control

- With Intelligent Key system: Refer to PCS-9, "POWER CONTROL SYSTEM : System Description".

- Without Intelligent Key system: Refer to PCS-41, "POWER CONTROL SYSTEM : System Description"

Compressor Control

DESCRIPTION

• BCM transmits the A/C ON signal and blower fan ON signal to ECM via CAN communication line only when the compressor operational condition is satisfied, and A/C indicator is turned ON.

Refer to BCS-13, "SIGNAL BUFFER SYSTEM : System Description" (with Intelligent Key system) or BCS- 103, "SIGNAL BUFFER SYSTEM : System Description" (without Intelligent Key system).

NOTE

:
Compressor operational condition • A/C switch signal: ON
• Blower fan ON signal: ON • Thermo control amp. signal: ON • ECM judges the conditions of each sensor (Refrigerant pressure sensor signal, accelerator position signal, etc.), and transmits the A/C compressor request signal to IPDM E/R via CAN communication line.

• By receiving the A/C compressor request signal from ECM, IPDM E/R turns the A/C relay to ON, and activates the compressor.

Refer to PCS-6, "RELAY CONTROL SYSTEM : System Description" (with Intelligent Key system) or PCS- 38, "RELAY CONTROL SYSTEM : System Description" (without Intelligent Key system).

CONTROL BY THERMO CONTROL AMP.

Low Temperature Protection Control • When the thermo control amp. detects that evaporator fin temperature is 2°C (36°F) or less, thermo control amp. signal becomes OFF, and stops the compressor.

• When the air temperature returns to 3.5°C (38°F) or more, the compressor is activated.

CONTROL BY ECM

Compressor Protection Control at Pressure Malfunction The high-pressure side value that is detected by refrigerant pressure sensor is as per the following state, ECM requests IPDM E/R to turn A/C relay OFF and stop the compressor.

• 3.12 MPa (31.82 kg/cm2, 452.4 psi) or more (When the engine speed is less than 1,500 rpm)
• 2.74 MPa (27.95 kg/cm2, 397.3 psi) or more (When the engine speed is 1,500 rpm or more)
• 0.14 MPa (1.43 kg/cm2, 20.3 psi) or less

Compressor Oil Circulation Control When the engine starts while the engine coolant temperature is 56°C (133°F) or less, ECM activates the compressor for approximately 6 seconds and circulates the compressor oil once.

Air Conditioning Cut Control When the engine condition is high load, ECM makes the A/C relay to OFF, and stops the compressor.

Refer to EC-60, "AIR CONDITIONING CUT CONTROL : System Description".

Door Control

SWITCHES AND THEIR CONTROL FUNCTIONS

1. Intake door
2. Blower motor
3. Air conditioner filter 4. Evaporator
5. Upper air mix door
6. Lower air mix door
7. Heater core
8. Foot door
9. Side ventilator door
10. Sub defroster door
11. Center ventilator and defroster door

Fresh air intake
Recirculation air
Defroster
Center ventilator
Side ventilator
Foot
Rear foot*

*: With rear foot duct

AIR DISTRIBUTION

Without rear foot duct

With rear foot duct