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Front Air Control Terminals and Reference ValueEJS003XJ
Measure voltage between each terminal and ground by following
Terminals and Reference Value for front air control.
PIN CONNECTOR TERMINAL LAYOUT
TERMINALS AND REFERENCE VALUE FOR FRONT AIR CONTROL
WJIA0544E
WJIA0402E
Te r m i -
nal No.Wire
colorItemIgnition
switchConditionVoltage (V)
(Approx.)
1 B Ground - - 0V
2 Y Sensor power ON - 5V
3 W/G Air mix door motor (Driver) CW ON Clockwise rotation Battery voltage
4 G Air mix door motor (Driver) CCW ON Counterclockwise rotation Battery voltage
5 BR/W Mode door motor CW ON Clockwise rotation Battery voltage
6 P/L Mode door motor CCW ON Counterclockwise rotation Battery voltage
7 O Intake door motor CCW ON Counterclockwise rotation Battery voltage
8 G/B Intake door motor CW ON Clockwise rotation Battery voltage
9 L/B Intake sensor ON - 0 - 5V
10 L/R Fan ON signalON Blower switch OFF 5V
ON Blower switch ON 0V
11 Y/B Rear defroster request ON - Battery voltage
12 W/R Compressor ON signalON A/C switch OFF 5V
ON A/C switch ON 0V
13 G/R Variable blower control ON - 0 - 5V
14 Y/G Power supply for IGN ON - Battery voltage
15 P Sensor ground ON - 0V
16 GR Mode door motor feedback ON - 0 - 5V
17 P Ambient sensor ON - 0 - 5V
18 SB Air mix door motor (Driver) feedback ON - 0 - 5V
19 LG Defroster door motor CW ON Clockwise rotation Battery voltage
20 P/B Defroster door motor CCW ON Counterclockwise rotation Battery voltage
21 V/R Sensor return ON - 0 - 5V
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11 . CHECK PBR FEEDBACK SIGNAL CIRCUIT FOR SHORT TO GROUND
1. Turn ignition switch OFF.
2. Disconnect front air control harness connector.
3. Check continuity between front air control harness connector
M49 terminal 16 and ground.
OK or NG
OK >> Replace front air control. Refer to ATC-147, "FRONT
AIR CONTROL" .
NG >> Repair or replace harness as necessary.
12. CHECK PBR FEEDBACK CIRCUIT FOR OPEN
1. Turn ignition switch OFF.
2. Disconnect the mode door motor harness connector and front
air control harness connector.
3. Check continuity between mode door motor harness connector
M142 terminal 2 and front air control harness connector M49 ter-
minal 16.
OK or NG
OK >> Replace mode door motor. Refer to ATC-165, "Removal
and Installation" .
NG >> Repair or replace harness as necessary.Continuity should not exist.
WJIA1733E
Continuity should exist.
LJIA0034E
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SYSTEM DESCRIPTION
Component Parts
Air mix door control system components are:
Front air control.
Air mix door motors (Driver, Passenger, and rear)
PBR (built-into air mix door motors)
In-vehicle sensor
Ambient sensor
Optical sensor
Intake sensor
System Operation
The front air control receives data from the temperature selected by the driver side, passenger side, and rear.
The front air control then applies a voltage to one circuit of the appropriate air mix door motor, while ground is
applied to the other circuit, causing the appropriate air mix door motor to rotate. The direction of rotation is
determined by which circuit has voltage applied to it, and which one has ground applied to it. The front air con-
trol monitors the air mix door positions by measuring the voltage signal on the PBR circuits of each door.
In AUTO mode the air mix, intake, mode door, and defrost door positions are set by the front air control which
determines the proper position based on inputs from the in-vehicle sensor, ambient sensor, optical sensor,
intake sensor, and the temperature selected by the driver and front and rear passengers.
Subsequently, HOT/COLD or DEFROST/VENT or FRESH/RECIRCULATION operation is selected. The new
door position data is returned to the front air control.
Air Mix Door Control Specification
WJIA1244E
WJIA0435E
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10. CHECK PBR FEEDBACK VOLTAGE
1. Reconnect the front air control harness connector.
2. Turn ignition switch ON.
3. Check voltage between front air control harness connector M49
terminal 18 and ground while rotating temperature control dial
from 32°C (90°F) to 16°C (60°F).
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 . CHECK PBR FEEDBACK SIGNAL CIRCUIT FOR SHORT TO GROUND
1. Turn ignition switch OFF.
2. Disconnect front air control harness connector.
3. Check continuity between front air control harness connector
M49 terminal 18 and ground.
OK or NG
OK >> Replace front air control. Refer to ATC-147, "FRONT
AIR CONTROL" .
NG >> Repair or replace harness as necessary.
12. CHECK PBR FEEDBACK CIRCUIT FOR OPEN
1. Turn ignition switch OFF.
2. Disconnect the air mix door motor (driver) harness connector
and front air control harness connector.
3. Check continuity between air mix door motor (driver) harness
connector M147 terminal 4 and front air control harness connec-
tor M49 terminal 18.
OK or NG
OK >> Replace air mix door motor (driver). Refer to ATC-166,
"FRONT AIR MIX DOOR MOTOR (DRIVER)" .
NG >> Repair or replace harness as necessary. Voltage : Approx. .5V - 4.5V
LJIA0041E
Continuity should not exist.
WJIA1739E
Continuity should exist.
WJIA0590E
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8. CHECK PBR REFERENCE VOLTAGE AND GROUND CIRCUITS
1. Turn ignition switch OFF.
2. Disconnect the front air control harness connector.
3. Check continuity between front air control harness connector
M49 terminal 2 and terminal 15.
OK or NG
OK >> GO TO 10.
NG >> GO TO 9.
9. CHECK PBR REFERENCE VOLTAGE CIRCUIT FOR OPEN
1. Disconnect the air mix door motor (passenger) harness connec-
tor.
2. Check continuity between air mix door motor (passenger) har-
ness connector M143 (B) terminal 3, 2 and front air control har-
ness connector M49 (A) terminal 2, 15.
OK or NG
OK >> Replace air mix door motor (passenger). Refer to AT C -
167, "FRONT AIR MIX DOOR MOTOR (PASSENGER)"
.
NG >> Repair or replace harness as necessary.
10. CHECK PBR FEEDBACK VOLTAGE
1. Reconnect the front air control harness connector.
2. Turn ignition switch ON.
3. Check voltage between front air control harness connector M50
terminal 41 and ground while rotating temperature control dial
(passenger) from 32°C (90°F) to 16°C (60°F).
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 . CHECK PBR FEEDBACK SIGNAL CIRCUIT FOR SHORT TO GROUND
1. Turn ignition switch OFF.
2. Disconnect front air control harness connector.
3. Check continuity between front air control harness connector
M50 terminal 41 and ground.
OK or NG
OK >> Replace front air control. Refer to ATC-147, "FRONT
AIR CONTROL" .
NG >> Repair or replace harness as necessary.Continuity should exist.
WJIA1731E
2 - 3 : Continuity should exist.
15 - 2 : Continuity should exist.
WJIA1777E
Voltage : Approx. .5V - 4.5V
LJIA0047E
Continuity should not exist.
WJIA1743E
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ATC-82
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10. CHECK PBR FEEDBACK VOLTAGE
1. Reconnect the front air control harness connector.
2. Turn ignition switch ON.
3. Check voltage between front air control harness connector M50
terminal 42 and ground while rotating temperature control dial
(rear) from maximum cold to maximum heat.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 . CHECK PBR FEEDBACK SIGNAL CIRCUIT FOR SHORT TO GROUND
1. Turn ignition switch OFF.
2. Disconnect front air control harness connector.
3. Check continuity between front air control harness connector
M50 terminal 42 and ground.
OK or NG
OK >> Replace front air control. Refer to ATC-147, "FRONT
AIR CONTROL" .
NG >> Repair or replace harness as necessary.
12. CHECK PBR FEEDBACK CIRCUIT FOR OPEN
1. Turn ignition switch OFF.
2. Disconnect the air mix door motor (rear) harness connector and
front air control harness connector.
3. Check continuity between air mix door motor (rear) harness con-
nector B155 terminal 4 and front air control harness connector
M50 terminal 42.
OK or NG
OK >> Replace air mix door motor (rear). Refer to ATC-167,
"REAR AIR MIX DOOR MOTOR" .
NG >> Repair or replace harness as necessary. Voltage : Approx. 1V - 4.5V
LJIA0053E
Continuity should not exist.
WJIA1749E
Continuity should exist.
LJIA0054E
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8. CHECK PBR REFERENCE VOLTAGE AND GROUND CIRCUITS
1. Turn ignition switch OFF.
2. Disconnect the front air control harness connector.
3. Check continuity between front air control harness connector
M49 terminal 2 and terminal 15.
OK or NG
OK >> GO TO 10.
NG >> GO TO 9.
9. CHECK PBR REFERENCE VOLTAGE CIRCUIT FOR OPEN
1. Disconnect the defroster door motor harness connector.
2. Check continuity between defroster door motor harness connec-
tor M144 (B) terminal 3, 2 and front air control harness connec-
tor M49 (A) terminal 2, 15.
OK or NG
OK >> Replace defroster door motor. Refer to ATC-163,
"Removal and Installation" .
NG >> Repair or replace harness as necessary.
10. CHECK PBR FEEDBACK VOLTAGE
1. Reconnect the front air control harness connector.
2. Turn ignition switch ON.
3. Check voltage between front air control harness connector M49
terminal 25 and ground while cycling defroster switch on and off.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 . CHECK PBR FEEDBACK SIGNAL CIRCUIT FOR SHORT TO GROUND
1. Turn ignition switch OFF.
2. Disconnect front air control harness connector.
3. Check continuity between front air control harness connector
M49 terminal 25 and ground.
OK or NG
OK >> Replace front air control. Refer to ATC-147, "FRONT
AIR CONTROL" .
NG >> Repair or replace harness as necessary.Continuity should exist.
WJIA1731E
2 - 3 : Continuity should exist.
15 - 2 : Continuity should exist.
WJIA1777E
Voltage : Approx. 1V - 4.5V
WJIA1786E
Continuity should not exist.
WJIA1787E
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5. CHECK FRONT BLOWER MOTOR RELAY (SWITCH SIDE) CIRCUIT FOR OPEN
Check continuity between front blower motor relay harness connec-
tor M107 terminal 3 (W/L) and front blower motor harness connector
M62 terminal 2 (W/L).
OK or NG
OK >> GO TO 6.
NG >> Repair harness or connector.
6. CHECK VARIABLE BLOWER CONTROL POWER SUPPLY CIRCUIT FOR OPEN
1. Disconnect variable blower control harness connector.
2. Check continuity between front blower motor relay harness con-
nector M107 terminals 3 (W/L) and variable blower control har-
ness connector M122 terminal 1 (W/L).
OK or NG
OK >> GO TO 7.
NG >> Repair harness or connector.
7. CHECK VARIABLE BLOWER CONTROL SIGNAL CIRCUIT
1. Disconnect front air control connector.
2. Check continuity between front air control harness connector
M49 terminal 13 (G/R) and variable blower control harness con-
nector M122 terminal 2 (G/R).
OK or NG
OK >> GO TO 8.
NG >> Repair harness or connector.
8. CHECK FRONT BLOWER MOTOR RELAY (COIL SIDE) POWER SUPPLY
1. Turn ignition switch ON.
2. Check voltage between front blower motor relay harness con-
nector M107 terminal 2 (Y/G) and ground.
OK or NG
OK >> GO TO 9.
NG >> Repair harness or connector.3 - 2 : Continuity should exist.
WJIA1360E
3 - 1 : Continuity should exist.
WJIA1361E
13 - 2 : Continuity should exist.
WJIA1362E
2 - Ground : Battery voltage.
WJIA1363E
