Page 492 of 3371

TROUBLE DIAGNOSIS
ATC-87
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
6. CHECK VARIABLE BLOWER CONTROL POWER SUPPLY CIRCUIT FOR OPEN
1. Disconnect variable blower control connector M122.
2. Check continuity between front blower motor relay harness con-
nector M107 terminals 3 (W/L) and 6 (W/L), and variable blower
control harness 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 M49.
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 1 (Y/G) and ground.
OK or NG
OK >> GO TO 9.
NG >> Repair harness or connector.
9. CHECK FRONT BLOWER MOTOR RELAY (COIL SIDE) GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Check continuity between front blower motor relay harness con-
nector M107 terminal 2 (R/B) and front air control harness con-
nector M49 terminal 26 (R/B).
OK or NG
OK >> Replace front air control. Refer to ATC-135, "FRONT
AIR CONTROL" .
NG >> Repair harness or connector.3, 6 - 1 : Continuity should exist.
WJIA0784E
13 - 2 : Continuity should exist.
WJIA0785E
1 - Ground : Battery voltage should exist.
WJIA0786E
2 - 26 : Continuity should exist.
WJIA0471E
Page 493 of 3371

ATC-88
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
10. REPLACE FUSES
1. Replace fuses.
2. Activate the front blower motor.
3. Do fuses blow?
YES or NO
YES >> GO TO 11.
NO >> Inspection End.
11 . CHECK FRONT BLOWER MOTOR POWER SUPPLY CIRCUIT FOR SHORT
1. Turn ignition switch OFF.
2. Disconnect variable blower control connector M122.
3. Check continuity between variable blower control harness con-
nector M122 terminal 1 (W/L) and ground.
OK or NG
OK >> GO TO 12.
NG >> Repair harness or connector.
12. CHECK VARIABLE BLOWER CONTROL SIGNAL CIRCUIT
1. Disconnect front air control connector M49.
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 >> Check blower motor, if OK replace variable blower con-
trol. Refer to ATC-89, "
Front Blower Motor" .
NG >> Repair harness or connector.1 - Ground. : Continuity should not exist.
WJIA0788E
13 - 2 : Continuity should exist.
WJIA0785E
Page 510 of 3371

TROUBLE DIAGNOSIS
ATC-105
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
SYSTEM DESCRIPTION
The front air control controls compressor operation based on ambient and intake temperature and a signal
from ECM.
Low Temperature Protection Control
The front air control will turn the compressor ON or OFF as determined by a signal detected by the intake sen-
sor and the ambient sensor.
When intake air temperature is higher than the preset value, the compressor turns ON. The compressor turns
OFF when intake air temperature is lower than the preset value. That preset value is dependent on the ambi-
ent temperature, refer to the following table.
DIAGNOSTIC PROCEDURE FOR MAGNET CLUTCH
SYMPTOM: Magnet clutch does not engage when A/C switch is ON.
1. CHECK INTAKE AND AMBIENT SENSOR CIRCUITS
Check intake and ambient sensors. Refer to ATC-53, "
A/C System Self-diagnosis Function" .
OK or NG
OK >> GO TO 2.
NG >>
Malfunctioning intake sensor. Refer to ATC-133, "Intake Sensor Circuit" .
Malfunctioning ambient sensor. Refer to ATC-125, "Ambient Sensor Circuit" .
Ambient temperature °C (°F)Co mp re s so r ON
intake temperature °C (°F)C o m p r e s s o r O F F
intake temperature °C (°F)
0 (32) 5.5 (41.9) 5.0 (41.0)
10 (50) 4.5 (40.1) 4.0 (39.2)
20 (68) 2.5 (36.5) 2.0 (35.6)
30 (86) 2.0 (35.6) 1.0 (33.8)
40 (104) 2.0 (35.6) 0.5 (32.9)
50 (122) 2.0 (35.6) 0.5 (32.9)
WJIA1369E
Page 511 of 3371

ATC-106
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
2. PERFORM AUTO ACTIVE TEST
Refer to PG-23, "
Auto Active Test" .
Does magnet clutch operate?
YES or NO
YES >>WITH CONSULT-II
GO TO 5.
WITHOUT CONSULT-II
GO TO 6.
NO >> Check 10A fuse (No. 42, located in IPDM E/R), and GO TO 3.
3. CHECK CIRCUIT CONTINUITY BETWEEN IPDM E/R AND COMPRESSOR
1. Turn ignition switch OFF.
2. Disconnect IPDM E/R connector E119 and compressor (magnet
clutch) connector F3.
3. Check continuity between IPDM E/R harness connector E119
terminal 11 (Y/B) and compressor harness connector F3 termi-
nal 1 (Y/B).
OK or NG
OK >> GO TO 4.
NG >> Repair harness or connector.
4. CHECK MAGNET CLUTCH CIRCUIT
Check for operation sound when applying battery voltage direct cur-
rent to terminal.
OK or NG
OK >> Replace IPDM E/R. Refer to PG-29, "Removal and
Installation of IPDM E/R" .
NG >> Replace magnet clutch. Refer to ATC-167, "
Removal
and Installation for Compressor Clutch" .
5. CHECK BCM INPUT (COMPRESSOR ON) SIGNAL
Check compressor ON/OFF signal. Refer to AT C - 3 3 , "
CONSULT-II
Function (BCM)" .
OK or NG
OK >> GO TO 8.
NG >> GO TO 6.
11 – 1 : Continuity should exist.
WJIA0808E
SJIA0197E
A/C SW ON : COMP ON SIG ON
A/C SW OFF : COMP ON SIG OFF
WJIA0469E
Page 512 of 3371

TROUBLE DIAGNOSIS
ATC-107
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
6. CHECK CIRCUIT CONTINUITY BETWEEN BCM AND FRONT AIR CONTROL
1. Turn ignition switch OFF.
2. Disconnect BCM connector M18 and front air control connector
M49.
3. Check continuity between BCM harness connector M18 terminal
27 (W/R) and front air control harness connector M49 terminal
12 (W/R).
OK or NG
OK >> GO TO 7.
NG >> Repair harness or connector.
7. CHECK VOLTAGE FOR FRONT AIR CONTROL (COMPRESSOR ON SIGNAL)
1. Reconnect BCM connector and front air control connector.
2. Turn ignition switch ON.
3. Check voltage between front air control harness connector M49
terminal 12 (W/R) and ground.
OK or NG
OK >> GO TO 8.
NG-1 >> If the voltage is approx. 5V when A/C switch is ON, replace front air control. Refer to ATC-135,
"FRONT AIR CONTROL" .
NG-2 >> If the voltage is approx. 0V when A/C switch is OFF, replace BCM. Refer to BCS-19, "
Removal
and Installation of BCM" . 27 - 12 Continuity should exist.
WJIA0809E
Te r m i n a l s
ConditionVoltag e
(Approx.) (+)
(-) Front air
control con-
nectorTe r m i n a l N o .
(Wire color)
M49 12 (W/R) GroundA/C switch: ON 0V
A/C switch: OFF 5V
WJIA0449E
Page 513 of 3371

ATC-108
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
8. CHECK REFRIGERANT PRESSURE SENSOR
WITH CONSULT-II
1. Start engine.
2. Check voltage of refrigerant pressure sensor. Refer to AT C - 3 3 , "
CONSULT-II Function (BCM)" .
WITHOUT CONSULT-II
1. Start engine.
2. Check voltage between ECM harness connector F54 terminal
70 (B/W) and ground.
OK or NG
OK >>WITH CONSULT-II
GO TO 9.
WITHOUT CONSULT-II
GO TO 10.
NG >> Refer to EC-607, "
REFRIGERANT PRESSURE SENSOR" .
9. CHECK BCM INPUT (FAN ON) SIGNAL
Check FAN ON/OFF signal while changing the front switch position.
Refer to ATC-33, "
CONSULT-II Function (BCM)" .
OK or NG
OK >> GO TO 12.
NG >> GO TO 10.
10. CHECK CIRCUIT CONTINUITY BETWEEN BCM AND FRONT AIR CONTROL
1. Turn ignition switch OFF.
2. Disconnect BCM connector M18 and front air control connector
M49.
3. Check continuity between BCM harness connector M18 terminal
28 (L/R) and front air control harness connector M49 terminal 10
(L/R).
OK or NG
OK >> GO TO 11.
NG >> Repair harness or connector.
Te r m i n a l s
Condition Voltage (+)
(-)
ECM con-
nectorTe r m i n a l N o .
(Wire color)
F54 70 (B/W) Ground A/C switch: ON Approx. 0.36 - 3.88V
LJIA0124E
FRONT FAN SWITCH ON : FAN ON SIG ON
FRONT FAN SWITCH OFF : FAN ON SIG OFF
WJIA0469E
28 - 10 Continuity should exist.
WJIA0450E
Page 514 of 3371
TROUBLE DIAGNOSIS
ATC-109
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
11 . CHECK VOLTAGE FOR FRONT AIR CONTROL (FAN ON SIGNAL)
1. Reconnect BCM connector and front air control connector.
2. Turn ignition switch ON.
3. Check voltage between front air control harness connector M49
terminal 10 (L/R) and ground.
OK or NG
OK >> Check CAN communication. Refer to ATC-32, "CAN Communication System Description" .
NG-1 >> If the voltage is approx. 5V when blower motor is ON, replace front air control. Refer to ATC-135,
"FRONT AIR CONTROL" .
NG-2 >> If the voltage is approx. 0V when blower motor is OFF, replace BCM. Refer to BCS-19, "
Removal
and Installation of BCM" .
Te r m i n a l s
ConditionVo ltag e
(Approx.) (+)
(-)
Front air con-
trol connectorTe r m i n a l N o .
(Wire color)
M49 10 (L/R) GroundA/C switch: ON
Blower motor
operates0V
A/C switch: OFF 5V
WJIA0451E
Page 608 of 3371

AUDIO
AV-21
C
D
E
F
G
H
I
J
L
MA
B
AV
Revision: August 20072004 QX56
44 (W) 43 (B)Audio right
channel
sound sig-
nal from sat-
ellite radio
tunerInput ONReceive audio
signalNo sound from satel-
lite radio tuner right
channel.
45 –Shield
ground
(audio sig-
nal)–– – 0V –
46 –Shield
ground
(data)–– – 0V –
48 (L) GroundSatellite
radio tuner
request to
audio unitInput ONTurn audio unit
ON 5VSatellite radio tuner
does not operate
properly.
49 (O/L) Ground Audio RX Input ONOperate audio
volume Satellite radio tuner
audio information
does not display
properly.
50 (W/L) Ground Audio TX Output ONOperate audio
volume Satellite radio tuner
audio information
does not display
properly.
65 (O/L) Ground Audio RX Input ONOperate audio
volume Audio does not oper-
ate properly.
66 (W/L) Ground Audio TX Output ONOperate audio
volume Audio does not oper-
ate properly.
67 – Shield – ON – 0VInterference and dis-
tortion heard from
speakers.
70 – Shield – – – 0VInterference and dis-
tortion heard from
speakers. Te r m i n a l
(Wire color)
ItemSignal
input/
outputCondition
Reference value
(Approx.)Example of symptom
+–Ignition
switchOperation
SKIA0177E
SKIA4403E
SKIA4402E
SKIA4403E
SKIA4402E