Toyota ST185 Series Repair Manual page 164

* MEDIUM SPEED OPERATION (OPERATION AT MANUAL M1, M2)
WHEN THE BLOWER SW (A/C CONTROL ASSEMBLY) IS MOVED TO M1 POSITION, CURRENT FLOWS FROM TERMINAL C3 OF A/C
CONTROL ASSEMBLY TO TERMINAL C10 OF A/C CONTROL ASSEMBLY
AS A RESULT, THE CURRENT FLOWING TO TERMINAL C2 OF THE A/C CONTROL ASSEMBLY FLOWS TO TERMINAL C10 OF THE A/C
CONTROL ASSEMBLY GROUND, TURNING THE BLOWER CONTROL RELAY ON SO THAT THE CURRENT FLOWING FROM THE
HEATER FUSE TO TERMINAL 5 OF THE HEATER REALY FLOWS TO TERMINAL 4 OF HEATER RELAY
MOTOR TERMINAL 1
TERMINAL 3 GROUND, CAUSING THE BLOWER MOTOR TO ROTATE AT MEDIUM SPEED.
WHEN THE BLOWER SW (A/C CONTROL ASSEMBLY) IS MOVED TO M2 POSITION, CURRENT FLOWS FROM TERMINAL 1 OF BLOWER
MOTOR TERMINAL 1 OF BLOWER RESISTOR
GROUND. THIS CURRENT FLOW FROM BLOWER MOTOR TO GROUND IS GREATER THAN AT M1 POSITION, SO THE BLOWER
MOTOR ROTATES AT MEDIUM HIGH SPEED.
3. OPERATION OF RECIRC/FRESH CONTROL SERVO MOTOR
(SWITCHING FROM FRESH TO RECIRC)
WITH IGNITION SW TURNED ON, THE CURRENT FLOWS FROM GAUGE FUSE TO TERMINAL 1 OF RECIRC/FRESH CONTROL SERVO
MOTOR. WHEN THE RECIRC/FRESH SW IS SWITCHED TO THE RECIRC SIDE, THE CURRENT FLOWS FROM TERMINAL 1 OF
RECIRC/FRESH CONTROL SERVO MOTOR
TERMINAL C10 GROUND. THE MOTOR ROTATES AND THE DAMPER MOVES TO THE RECIRC SIDE.
WHEN IT IS IN THE RECIRC POSITION, THE CURRENT IS CUT INSIDE THE SERVO MOTOR AND THE DAMPER STOPS AT THAT
POSITION.
(SWITCHING FROM RECIRC TO FRESH)
WITH IGNITION SW ON, WHEN THE RECIRC/FRESH SW IS SWITCHED TO THE FRESH SIDE, THE CURRENT FLOWS FROM TERMINAL
1 OF RECIRC/FRESH CONTROL SERVO MOTOR
MOTOR ROTATES AND THE DAMPER MOVES TO THE FRESH SIDE. WHEN IT IS IN THE FRESH POSITION, THE CURRENT IS CUT
INSIDE THE SERVO MOTOR AND THE DAMPER STOPS AT THAT POSITION.
SERVICE HINTS
A/C MAGNET CLUTCH
A 4
4–GROUND : APPROX. 3.7 W
A/C PRESSURE SW
A 5
3–2 : OPEN ABOVE APPROX. 13.5 KG/CM
CLOSED BELOW APPROX. 10 KG/CM
1–4 : OPEN WITH PRESSURE LESS THAN 2.1 KG/CM
A/C AMPLIFIER
A18
8–15 : CONTINUITY WITH A/C SW (A/C CONTROL ASSEMBLY) ON AND IGNITION SW ON POSITION
14–15 : ALWAYS CONTINUITY
14–GROUND: ALWAYS CONTINUITY
15–GROUND: ALWAYS CONTINUITY
13–GROUND: APPROX. 12 VOLTS WITH IGNITION SW ON
A/C THERMISTOR
A26
: APPROX. 4852 Ω AT 0°C (32°F)
1–2
APPROX. 2341 Ω AT 15°C (59°F)
APPROX. 1500 Ω AT 25°C (77°F)
AIR MIX CONTROL SERVO MOTOR
A29
2–GROUND : APPROX. 12 VOLTS WITH TEMPERATURE CONTROL VOLUME AT WARM TO COOL POSITION
6–GROUND : APPROX. 12 VOLTS WITH TEMPERATURE CONTROL VOLUME AT COOL TO WARM POSITION
1–3 : ALWAYS APPROX. 6 KΩ
BLOWER CONTROL RELAY
B 3
3–4 : CLOSED WITH BLOWER SW (A/C CONTROL ASSEMBLY) AT HI POSITION
1–3 : CLOSED WITH BLOWER SW (A/C CONTROL ASSEMBLY) AT M1 POSITION
2–3 : CLOSED WITH BLOWER SW (A/C CONTROL ASSEMBLY) AT M2 POSITION
BLOWER RESISTOR
B 5
1–3 : APPROX. 0.48 Ω
3–2 : APPROX. 0.94 Ω
2–4 : APPROX. 0.91 Ω
WATER TEMP. SW (FOR FANS CONTROL)
W 3
1–2 : OPEN ABOVE APPROX. 90°C (194°F)
CLOSED BELOW APPROX. 83°C (181.4°F)
TERMINAL 1 OF BLOWER RESISTOR
TERMINAL 3
TERMINAL 2
TERMINAL 3
2 (192 PSI, 1323 KPA)
(142 PSI, 980 KPA)
2
2 (
GROUND AND TURNS THE HEATER RELAY ON.
TERMINAL 2
TERMINAL 2 OF BLOWER CONTROL RELAY
TERMINAL A18 OF RECIRC/FRESH CONTROL SERVO MOTOR
TERMINAL C10 OF A/C CONTROL ASSEMBLY
30 PSI, 206 KPA ) OR ABOVE 27 KG/CM
TERMINAL 2 OF BLOWER
TERMINAL 7 OF BLOWER CONTROL RELAY
2
(384 PSI, 2648 KPA)
TERMINAL 3
GROUND, THE
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