Toyota MCV10 Automobile User Manual


 
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FAN MOTOR OPERATION
WITH THE IGNITION SW IS TURNED ON, CURRENT FLOWS FROM ECU–IG FUSE TO RADIATOR FAN RELAY NO. 1 (COIL SIDE) AND
RADIATOR FAN RELAY NO. 2 (COIL SIDE) TERMINAL 2 OF THE A/C SINGLE PRESSURE SW TERMINAL 3 TERMINAL 2 OF THE
WATER TEMP. SW TERMINAL 1 GROUND, AND RADIATOR FAN RELAY NO. 1 AND NO. 2 ARE TURNED ON.
RADIATOR FAN MOTOR OPERATION
WHEN THE IGNITION SW IS TURNED ON, RADIATOR FAN RELAY NO. 1 IS TURNED ON. IF AT THIS TIME THE ENGINE COOLANT
TEMPERATURE IS APPROX. 90°C (194°F) OR HIGHER, THE WATER TEMP. SW IS TURNED OFF, RADIATOR FAN RELAY NO. 1 IS
TURNED OFF.
AS A RESULT, CURRENT FROM THE RDI FAN FUSE TO RADIATOR FAN RELAY NO. 1 (POINT SIDE) TERMINAL 2 OF THE
RADIATOR FAN MOTOR TERMINAL 1 GROUND, THUS ACTIVATING THE ROTATION OF THE RADIATOR FAN MOTOR.
LOW SPEED OPERATION
WHEN THE IGNITION SW IS TURNED ON AND THE A/C ACTIVATED, RADIATOR FAN RELAY NO. 1 AND RADIATOR FAN RELAY NO. 2
ARE TURNED ON, CURRENT FLOWS FROM A/C MAGNETIC CLUTCH RELAY (POINT SIDE) TO RADIATOR FAN RELAY NO. 3 (COIL
SIDE) GROUND, AND RADIATOR FAN RELAY NO. 3 IS TURNED ON.
AS A RESULT, CURRENT FLOWS FROM CDS FAN FUSE TO TERMINAL 2 OF THE A/C CONDENSER FAN MOTOR TERMINAL 1
RADIAOTR FAN RELAY NO. 2 (POINT SIDE) RADIATOR FAN RELAY NO. 3 (POINT SIDE) TERMINAL 2 OF THE RADIATOR FAN
MOTOR TERMINAL 1 GROUND, FLOWING TO EACH FAN MOTOR IN SERIES, CAUSING THE FAN TO AT LOW SPEED.
HIGH SPEED OPERATION OF THE FAN MOTOR DUARING A/C OPERATION
WHEN THE A/C OPERATION, THE REFRIGERRANT PRESSURE BECOME HIGHER THAN OR DINARY LEVEL (APPROX. 15.58 KG/CM
2
(221.2 PSI, 1527 KPA)) THE A/C SINGLE PRESSURE SW IS TURNED OFF. AS A RESULT, RADIATOR FAN RELAY NO. 1 AND RADIATOR
FAN RELAY NO. 2 ARE TURNED OFF, AND CURRENT FLOWS FROM RDI FUSE TO RADIATOR FAN RELAY NO. 1 (POINT SIDE)
TERMINAL 2 OF THE RADIATOR FAN MOTOR TERMINAL 1 GROUND, AND CURRENT FLOWS FROM CDS FAN FUSE TO
TERMINAL 2 OF THE A/C CONDENSER FAN MOTOR TERMINAL 1 RADIATOR FAN RELAY NO. 2 (POINT SIDE) GROUND, AND
TO EACH FAN MOTOR IN PARALLEL, THUS CAUSING THE FAN MOTORS OPERATE HIGH SPEED.
NOTE THAT, BECAUSE THE CURRENT FLOWS IN THE SAME MENNER EVEN IF THE ENGINE COOLANT TEMPERATURE IS APPROX.
90°C (194°F) OR HIGHER, THE FAN MOTOR OPERATE AT HIGH SPEED.
A 2 A/C SINGLE PRESSURE SW
2–3 : OPEN ABOVE APPROX. 15.58 KG/CM
2
(221.2 PSI, 1527 KPA)
CLOSE BELOW APPROX. 15.56 KG/CM
2
(178.4 PSI, 1231 KPA)
21
21
A1 R1BLACK GRAY
12
E5A2 BLACK
23
SYSTEM OUTLINE
SERVICE HINTS