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AIR CONDITIONER CONTROLATC-31
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Revision: November 2009 2006 QX56
System Description (Front)EJS003XA
SWITCHES AND THEIR CONTROL FUNCTION
WJIA1680E
WJIA1237E
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ATC-32
AIR CONDITIONER CONTROL
Revision: November 20092006 QX56
System Description (Rear)EJS003XB
SWITCHES AND THEIR CONTROL FUNCTION
WJIA0623E
WJIA1067E
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AIR CONDITIONER CONTROLATC-33
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Revision: November 2009 2006 QX56
CAN Communication System DescriptionEJS003XC
Refer to LAN-26, "CAN COMMUNICATION" .
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ATC-38
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
DATA MONITOR
Operation Procedure
1. Touch “AIR CONDITIONER” on “SELECT TEST ITEM” screen.
2. Touch “DATA MONITOR ” on “SELECT DIAG MODE ” screen.
3. Touch either “ALL SIGNALS ” or “SELECTION FROM MENU” on
“DATA MONITOR ” screen.
4. When “SELECTION FROM MENU” is selected, touch items to
be monitored. When "ALL SIGNALS ” is selected, all the items
will be monitored.
5. Touch “START”.
6. Touch “RECORD” while monitoring, then the status of the moni-
tored item can be recorded. To stop recording, touch “STOP”.
Display Item List
WJIA0468E
BCIA0031E
ALL SIGNALS Monitors all the items.
SELECTION FROM MENU Selects and monitors the individual item selected.
WJIA0469E
Monitor item name “ operation or
unit ” Contents
IGN ON SW “ON/OFF ”Displays “IGN Position (ON)/OFF, ACC Position (OFF) ” status as judged from ignition switch signal.
COMP ON SIG “ON/OFF ”Displays “COMP (ON)/COMP (OFF) ” status as judged from air conditioner switch signal.
FAN ON SIG “ON/OFF ”Displays “FAN (ON)/FAN (OFF) ” status as judged from blower motor switch signal.
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ATC-54
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
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
color ItemIgnition
switch Condition Voltage (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 rotationBattery voltage
6 P/L Mode door motor CCW ON Counterclockwise rotationBattery voltage
7 O Intake door motor CCW ON Counterclockwise rotationBattery voltage
8 G/B Intake door motor CW ON Clockwise rotationBattery voltage
9 L/B Intake sensor ON- 0 - 5V
10 L/R Fan ON signal ON Blower switch OFF
5V
ON Blower switch ON 0V
11 Y/B Rear defroster request ON- Battery voltage
12 W/R Compressor ON signal ON 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 rotationBattery voltage
20 P/B Defroster door motor CCW ON Counterclockwise rotationBattery voltage
21 V/R Sensor return ON- 0 - 5V
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TROUBLE DIAGNOSISATC-55
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22 Y/R Power supply for BAT-- Battery voltage
23 R/L Illumination + ON Park lamps ONBattery voltage
24 BR Illumination - - Park lamps ON
25 LG/B Defroster door motor feedback ON -0 - 5V
26 R/B Front blower request ONFront blower motor OFF
Battery voltage
Front blower motor ON 0V
27 GR/R Air mix door motor (Rear) CW ON Clockwise rotationBattery voltage
28 L/Y Air mix door motor (Rear) CCW ON Counterclockwise rotation Battery voltage
29 Y/L Water valve ONWater valve open
0V
Water valve closed 5V
30 W/G Water valve ONWater valve open
0V
Water valve closed Battery voltage
31 W/V Optical sensor (Passenger) ON- 0 - 5V
32 LG/R In-vehicle sensor signal ON- 0 - 5V
33 V Air mix door (Rear) set point ON- 0 - 5V
34 L CAN-H ON- 0 - 5V
35 P CAN-L ON- 0 - 5V
36 G/W Air mix door motor (Passenger) CW ON Clockwise rotation Battery voltage
37 L Air mix door motor (Passenger)
CCW ON Counter clockwise rotation
Battery voltage
38 W/L Rear blower request ONFront blower motor OFF
Battery voltage
Front blower motor ON 0V
39 Y/B Rear select signal ON- 0V - Battery voltage
40 G/O Optical sensor (Driver) ON- 0 - 5V
41 R/W Air mix door motor (Passenger)
feedback ON
- 0 - 5V
42 R/Y Air mix door motor (Rear) feedback ON -0 - 5V
43 BR/Y In-vehicle sensor motor (+) ON- Battery voltage
44 O/B In-vehicle sensor motor (-) ON- 0V
Te r m i -
nal No. Wire
color Item
Ignition
switch Condition
Voltage (V)
(Approx.)
PIIA2344E
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ATC-58
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
Operational Check (Front)EJS003XL
The purpose of the operational check is to confirm that the system operates properly.
CHECKING MEMORY FUNCTION
1. Set the temperature to 90°F or 32 °C.
2. Turn front blower control dial counterclockwise until system shuts OFF.
3. Turn ignition switch OFF.
4. Turn ignition switch ON.
5. Press the AUTO switch.
6. Confirm that the set temperature remains at previous temperature.
7. Turn front blower control counterclockwise until system shuts OFF.
If NG, go to trouble diagnosis procedure for ATC-131, "
Memory Function" .
If OK, continue with next check.
CHECKING BLOWER
1. Turn front blower control clockwise, blower should operate on low speed. The blower symbol should have one blade lit (on display).
2. Turn the front blower control dial again, and continue checking blower speed and blower symbol until all speeds are checked.
3. Leave blower on MAX speed.
If NG, go to trouble diagnosis procedure for AT C - 9 5 , "
DIAGNOSTIC PROCEDURE FOR BLOWER
MOTOR"AT C - 9 5 , "DIAGNOSTIC PROCEDURE FOR BLOWER MOTOR" .
If OK, continue with next check.
CHECKING DISCHARGE AIR
1. Press MODE switch four times and the DEF ( ) switch.
2. Each position indicator should change shape (on display).
3. Confirm that discharge air comes out according to the air distribution table. Refer to AT C - 3 0 , "
Discharge
Air Flow" .
Mode door position is checked in the next step.
If NG, go to trouble diagnosis procedure for AT C - 6 4 , "
Mode Door Motor Circuit" .
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or visual inspection) and intake door position is at fresh
when the DEF or D/F is selected.
CHECKING RECIRCULATION (, ONLY)
1. Press recirculation ( ) switch one time. Recirculation indicator should illuminate.
2. Press recirculation ( ) switch one more time. Recirculation indicator should go off.
3. Listen for intake door position change (blower sound should change slightly).
If NG, go to trouble diagnosis procedure for AT C - 8 3 , "
Intake Door Motor Circuit" .
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or visual inspection) and intake door position is at fresh
when the DEF or D/F is selected. REC ( ) is not allowed in DEF ( ) D/F ( ) or FOOT ( ).
CHECKING TEMPERATURE DECREASE
1. Rotate temperature control dial (driver side or passenger side) counterclockwise until 16 °C (60 °F) is dis-
played.
2. Check for cold air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation. If OK, go to trouble diagnosis procedure for ATC-121,
"Insufficient Cooling" . If air mix door motor appears to be malfunctioning, go to AT C - 7 2 , "DIAGNOSTIC PRO-
CEDURE FOR AIR MIX DOOR MOTOR (DRIVER)" or AT C - 7 6 , "DIAGNOSTIC PROCEDURE FOR AIR MIX
DOOR MOTOR (PASSENGER)" .
If OK, continue the check. Conditions : Engine running and at normal operating temperature
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TROUBLE DIAGNOSISATC-59
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Revision: November 2009 2006 QX56
CHECKING TEMPERATURE INCREASE
1. Rotate temperature control dial clockwise (driver side or passenger side) until 32°C (90 °F) is displayed.
2. Check for hot air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation. If OK, go to trouble diagnosis procedure for ATC-128,
"Insufficient Heating" . If air mix door motor appears to be malfunctioning, go to AT C - 7 2 , "DIAGNOSTIC PRO-
CEDURE FOR AIR MIX DOOR MOTOR (DRIVER)" or AT C - 7 6 , "DIAGNOSTIC PROCEDURE FOR AIR MIX
DOOR MOTOR (PASSENGER)" .
If OK, continue with next check.
CHECK A/C SWITCH
1. Press A/C switch when AUTO switch is ON, or in manual mode.
2. A/C switch indicator will turn ON.
Confirm that the compressor clutch engages (sound or visual inspection).
NOTE:
If current mode setting is DEF or D/F, compressor clutch may already be engaged.
If NG, go to trouble diagnosis procedure for AT C - 11 5
.
If OK, continue with next check.
CHECKING AUTO MODE
1. Press AUTO switch.
2. Display should indicate AUTO.
If ambient temperature is warm, and selected temperature is cool, confirm that the compressor clutch
engages (sound or visual inspection). (Discharge air and blower speed will depend on ambient, in-vehi-
cle, and set temperatures.)
If NG, go to trouble diagnosis procedure for AT C - 6 1 , "
Power Supply and Ground Circuit for Front Air Control" ,
then if necessary, trouble diagnosis procedure for AT C - 11 5 , "
Magnet Clutch Circuit" .
If all operational checks are OK (symptom cannot be duplicated), go to malfunction Simulation Tests in AT C -
39, "How to Perform Trouble Diagnosis for Quick and Accurate Repair" and perform tests as outlined to simu-
late driving conditions environment. If symptom appears. Refer to AT C - 3 9 , "
How to Perform Trouble Diagnosis
for Quick and Accurate Repair" , AT C - 3 9 , "SYMPTOM TABLE" and perform applicable trouble diagnosis pro-
cedures.