2004 INFINITI QX56 Ins

ATC-100
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
Rear Blower Motor
Check that there are no foreign particles inside the intake unit.
Apply 12 volts to terminal 2 and ground to terminal 1 and ensure that
the blower motor rotates freely and quietly.
Rear Blower Motor Resistor
Check continuity between terminals. There will be resistance, but
there should not be an open or short between any two terminals.
WJIA0898E
LJ IA0116E

TROUBLE DIAGNOSIS
ATC-101
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
Rear Air Control CircuitEJS002CK
SYMPTOM:

Temperature cannot be adjusted from the rear air control.
INSPECTION FLOW
*1ATC-59, "Operational Check (Rear)"*2AT C - 5 3 , "A/C System Self-diagno-
sis Function"
*3AT C - 5 5 , "SELF-DIAGNOSIS CODE
CHART"
*4ATC-102, "DIAGNOSTIC PROCE-
DURE FOR REAR AIR CONTROL"
*5AT C - 7 3 , "DIAGNOSTIC PROCE-
DURE FOR AIR MIX DOOR
MOTOR (REAR)"
WJIA0801E

ATC-104
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
Magnet Clutch CircuitEJS002CL
SYMPTOM: Magnet clutch does not engage.
INSPECTION FLOW
*1AT C - 5 6 , "Operational Check (Front)"*2ATC-53, "A/C System Self-diagnosis
Function"
*3AT C - 5 5 , "SELF-DIAGNOSIS CODE
CHART"
*4ATC-125, "Ambient Sensor Circuit"*5ATC-133, "Intake Sensor Circuit"*6AT C - 3 5 , "SYMPTOM TABLE"
WJIA0962E

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

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

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

ATC-110
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
Insufficient CoolingEJS002CM
SYMPTOM: Insufficient cooling
INSPECTION FLOW
*1 .AT C - 5 6 , "Operational Check
(Front)"
*2AT C - 5 3 , "A/C System Self-diagno-
sis Function"
*3AT C - 5 5 , "SELF-DIAGNOSIS CODE
CHART"
*4 EC-410, "SYSTEM DESCRIPTION"*5AT C - 5 , "Contaminated Refrigerant"*6 .AT C - 111 , "PERFORMANCE TEST
DIAGNOSES"
*7ATC-113, "Test Reading"*8MA-12, "Checking Drive Belts"*9ATC-121, "Water Valve Circuit"
WJIA0963E

ATC-112
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
*1ATC-167, "Removal and Installation
for Compressor Clutch"
*2ATC-83, "Front Blower Motor Circuit"*3MA-12, "Checking Drive Belts"
WJIA0361E