CLIMATE CONTROL UNIT [MANUAL AIR CONDITIONER]


id0740a2320100


Purpose

•  The climate control unit performs air conditioning according to the operation by the users and the driving conditions of the vehicle.

Function

•  The climate control unit determines optimum air-conditioning based on the input signals from each sensor and the control module and the operation signals from the control panel, and controls each actuator, A/C compressor, and the blower motor. (See MANUAL AIR CONDITIONER CONTROL SYSTEM [MANUAL AIR CONDITIONER].)

Construction

•  A logic-type climate control unit has been adopted.
•  The climate control unit consists of a control panel and a control unit.
•  The switches and dials shown in the figure are positioned on the control panel.
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Fail-safe

•  If a malfunction is detected by the malfunction detection function, the fail-safe function performs the following controls to prevent an operation malfunction of the manual air conditioner and malfunction of output devices.

Fail-safe function table

Part where malfunction is determined

Malfunction determined when IG SW at ON

Malfunction already exists when IG SW turned to ON

Ambient temperature sensor
Ambient temperature sensor input value is fixed at the value right before the malfunction.
Ambient temperature sensor input value is fixed at 15 °C {59 °F}.
Evaporator temperature sensor
A/C output OFF is controlled when the evaporator temperature sensor input value is at 0 °C {32 °F}.
Engine coolant temperature sensor
Engine coolant temperature sensor input value is fixed at 85 °C {185 °F}.
Air mix actuator
(potentiometer)
Air mix actuator drive signal is stopped right when the malfunction is determined.
However, it is fixed at MAX COLD when the manually set temperature is at 15°C {60 °F} and fixed at MAX HOT when the manually set temperature is at 29°C {84 °F}.
Control based on ambient temperature.
(See Graph 1.)
However, it is fixed at MAX COLD when the manually set temperature is at 15°C {60 °F} and fixed at MAX HOT when the manually set temperature is at 29°C {84 °F}.
Airflow mode actuator
(potentiometer)
Airflow mode actuator drive signal is stopped right when the malfunction is determined.
•  However, change the operation to VENT or DEF when the manual operation selected to VENT or DEF.
Control based on ambient temperature.
(See Graph 2.)
•  However, change the operation to VENT or DEF when the manual operation selected to VENT or DEF.
Air mix actuator
(motor lock)
•  Air mix actuator drive signal is stopped right when the malfunction is determined.
•  Twenty seconds after ignition is switched ON, the air mix actuator drive signal is output normally again. Afterwards, motor output is stopped during malfunction determination.
Airflow mode actuator
(motor lock)
•  Airflow mode actuator drive signal is stopped right when the malfunction is determined.
•  Nine seconds after ignition is switched ON, the airflow mode actuator drive signal is output normally again. Afterwards, motor output is stopped during malfunction determination.

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