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ATC-54
TROUBLE DIAGNOSIS
Revision: October 2005 2005 QX56
22 Y/R Power supply for BAT - - Battery voltage
23 R/L Illumination + ON Park lamps ON Battery 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 rotation Battery voltage
28 L/Y Air mix door motor (Rear) CCW ON Counterclockwise rotation Battery voltage
29 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 LAir mix door motor (Passenger)
CCWON 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/WAir mix door motor (Passenger)
feedbackON - 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
colorItemIgnition
switchConditionVoltage (V)
(Approx.)
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TROUBLE DIAGNOSIS
ATC-55
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Revision: October 20052005 QX56
A/C System Self-diagnosis FunctionEJS003XK
DESCRIPTION
The self-diagnostic system diagnoses sensors, door motors, blower motor, etc. Refer to applicable sections
(items) for details. Fault codes (if any are present) will be displayed in the ambient temperature display area.
Refer to AT C - 5 6 , "
SELF-DIAGNOSIS CODE CHART" .
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ATC-56
TROUBLE DIAGNOSIS
Revision: October 20052005 QX56
SELF-DIAGNOSIS CODE CHART
Code No. Reference page
02 EE changed by calibrationATC-147, "
FRONT AIR CONTROL"
03 Battery voltage out of rangeSC-4, "BATTERY"
12 Air mix door motor (Passenger) circuit failureAT C - 7 6 , "DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR
MOTOR (PASSENGER)"
20 BCM not responding to A/C requestAT C - 11 6 , "DIAGNOSTIC PROCEDURE FOR MAGNET
CLUTCH"
21 BCM not responding to rear defroster requestGW-77, "REAR WINDOW DEFOGGER"
22 Air mix door motor (Driver) circuit failureAT C - 7 2 , "DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR
MOTOR (DRIVER)"
30 In-vehicle sensor circuit out of range (low)
ATC-145, "Intake Sensor Circuit"31 In-vehicle sensor circuit out of range (high)
38 Air mix door motor (rear) circuit failureAT C - 7 9 , "
DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR
MOTOR (REAR)"
40 Ambient sensor circuit short
ATC-137, "Ambient Sensor Circuit"41 Ambient sensor circuit open
44 In-vehicle sensor motor circuit open
ATC-145, "
Intake Sensor Circuit"46 In-vehicle sensor motor circuit short
50 Optical sensor (Driver) circuit open or short
ATC-143, "
Optical Sensor Circuit"52 Optical sensor (Passenger) circuit open or short
56 Intake sensor circuit short
ATC-145, "
Intake Sensor Circuit"57 Intake sensor circuit open
62 Defroster door motor circuit failureAT C - 8 7 , "
Defroster Door Motor Circuit"
80 CAN bus faultLAN-5, "CAN COMMUNICATION"
82 Intake door motor (driver) circuit malfunctionAT C - 8 5 , "DIAGNOSTIC PROCEDURE FOR INTAKE DOOR
MOTOR"
90 Stuck buttonATC-147, "FRONT AIR CONTROL"
92 Mode door motor circuit failureAT C - 6 4 , "Mode Door Motor Circuit"
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TROUBLE DIAGNOSIS
ATC-57
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Revision: October 20052005 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 tempera-
ture.
7. Turn front blower control counterclockwise until system shuts
OFF.
If NG, go to trouble diagnosis procedure for ATC-133, "
Memory
Function" .
If OK, continue with next check.
CHECKING BLOWER
1. Press the AUTO switch. 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"ATC-95, "DIAGNOSTIC
PROCEDURE FOR BLOWER MOTOR" .
If OK, continue with next check.Conditions : Engine running and at normal operating temperature
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ATC-58
TROUBLE DIAGNOSIS
Revision: October 20052005 QX56
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 distri-
bution table. Refer to ATC-29, "
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
1. Press recirculation ( ) switch one time. Recirculation indica-
tor 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 ATC-83, "
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.
CHECKING TEMPERATURE DECREASE
1. Rotate temperature control dial (driver side or passenger side)
counterclockwise until 16°C (60°F) is displayed.
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 ATC-72,
"DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR
(DRIVER)" or AT C - 7 6 , "DIAGNOSTIC PROCEDURE FOR AIR MIX
DOOR MOTOR (PASSENGER)" .
If OK, continue the check.
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TROUBLE DIAGNOSIS
ATC-59
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Revision: October 20052005 QX56
CHECKING TEMPERATURE INCREASE
1. Rotate temperature control dial clockwise (driver side or passen-
ger 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 PROCEDURE 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).
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-vehicle, and set temperatures.)
If NG, go to trouble diagnosis procedure for ATC-61, "
Power Supply
and Ground Circuit for Front Air Control" , then if necessary, trouble
diagnosis procedure for ATC-115, "
Magnet Clutch Circuit" .
If all operational checks are OK (symptom cannot be duplicated), go
to malfunction Simulation Tests in ATC-38, "
How to Perform Trouble
Diagnosis for Quick and Accurate Repair" and perform tests as out-
lined to simulate driving conditions environment. If symptom appears. Refer to AT C - 3 8 , "
How to Perform Trou-
ble Diagnosis for Quick and Accurate Repair" , ATC-38, "SYMPTOM TABLE" and perform applicable trouble
diagnosis procedures.
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ATC-60
TROUBLE DIAGNOSIS
Revision: October 20052005 QX56
Operational Check (Rear)EJS003XM
The purpose of the operational check is to confirm that the system operates properly.
CHECKING BLOWER
1. Turn the rear blower control dial to switch position "1". Blower
should operate on low speed.
2. Turn the rear blower control dial counterclockwise to switch
position "2", "3", and "4" until all speeds are checked.
3. Leave blower on MAX speed.
If NG, go to trouble diagnosis procedure for ATC-101, "
Rear Blower
Motor Circuit" .
If OK, continue the check.
CHECKING TEMPERATURE DECREASE
1. Rotate temperature and mode dial fully counterclockwise.
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 ATC-79,
"DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR
(REAR)" .
If OK, continue the check.
CHECKING TEMPERATURE INCREASE
1. Rotate temperature and mode dial clockwise.
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 ATC-79,
"DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR
(REAR)" .
If OK, continue the check.Conditions : Engine running and at normal operating temperature
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TROUBLE DIAGNOSIS
ATC-61
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Revision: October 20052005 QX56
Power Supply and Ground Circuit for Front Air ControlEJS003XN
SYMPTOM: A/C system does not come on.
INSPECTION FLOW
*1ATC-61, "Power Supply and Ground
Circuit for Front Air Control"
*2AT C - 5 7 , "Operational Check (Front)"
or AT C - 6 0 , "
Operational Check
(Rear)"
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