Toyota SV25 Automobile User Manual


 
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RADIATOR FAN AND AIR CONDITIONER (2VZ–FE)
5. AIR CONDITIONER OPERATION
WHEN THE BLOWER SW IS SET TO ON, CURRENT FROM THE 30A HEATER CB FLOWS THROUGH TERMINAL I14 (PUSH SWITCH
TYPE), 5 (LEVER SWITCH TYPE) OF THE A/C SW, TERMINAL 1 OF THE A/C DUAL PRESSURE SW TERMINAL 2 TERMINAL 14 OF
THE A/C AMPLIFIER, TERMINAL 1 OF THE MAGNET CLUTCH RELAY VIA THE A/C FUSE. THE ENGINE SPEED SIGNAL FROM IGNITER,
THE EVAPORATOR TEMP. SIGNAL FROM THE A/C THERMISTOR, AND THE LOCK SIGNAL FROM THE A/C COMPRESSOR ARE ALL
SUPPLIED TO THE A/C AMPLIFIER. WHEN THE A/C SW IS TURNED ON, THE A/C SW ON SIGNAL IS SENT TO THE A/C AMPLIFIER,
ACTIVATING IT AND TURNING ON THE MAGNET CLUTCH RELAY, SO THAT CURRENT FLOWS FROM TERMINAL 1 OF THE RELAY
TERMINAL 2 MAGNET CLUTCH, CAUSING THE COMPRESSOR TO OPERATE, THEN THE MAGNET CLUTCH ACTIVATING THE
COMPRESSOR. THE A/C OPERATION IS SHUT OFF WHEN A SIGNAL INDICATING LOW EVAPORATOR TEMP., GREAT DIFFERENCE
BETWEEN THE ENGINE AND COMPRESSOR SPEEDS, HIGH WATER TEMP. SIGNAL, OR ABNORMALLY HIGH OR LOW REFRIGERANT
PRESSURE, IS SUPPLIED WHILE THE ENGINE HIGH SPEED SIGNAL EXISTS. WHEN ONE OF THESE SIGNALS IS RECEIVED, THE
AMPLIFIER SHUTS OFF THE A/C OPERATION.
WHEN THE DIFFERENCE BETWEEN THE ENGINE AND COMPRESSOR SPEED IS EXCESSIVE, THE AMPLIFIER TURNS ON THE A/C
SW INDICATOR LIGHT TO INDICATE A FAULT.